History and Introduction to Computers



Basic Computer Troubleshooting

This lesson is a brief overview about the history of computers. It also discusses the types and functioning of the main components of a computer.

Introduction to Computers:

 

History of Computers:

 

A computer is an electronic device capable of executing instructions and transforming information from one form to another.

Computer Generations:

The existence of computers dates back to older times. According to some sources, it started with the creation of abacus, a simple counting aid or mathematical device that was probably invented in Babylonia (now called Iraq) in the fourth century B.C.

The First Generation of Computers:

The first real electronic computer or the first generation computer was actually introduced in 1950's. All computers of this generation used vacuum tubes to perform calculations. These types of computers had certain disadvantages like all of them were very big machines and therefore, needed big rooms to house them with air conditioning because of the large amounts of heat generated by the vacuum tubes. Not only this, but they were very expensive as well because a lot of skill and effort is needed in making vacumm tubes and they can easily burn out with heat.  Following this, the development in the electronic components helped in the development of digital computers also.

Second Generation Computers:

Then came the second-generation computers that used transistors and were first introduced in the late 1950's and early 1960's. They were smaller, faster and more reliable than the first generation computers. This was the time when computers became common in large businesses and universities. Transistor is actually a device that is composed of a semiconductor material used to amplify a signal or open or close a circuit. Second generation computers used transistors made out of silicon. These computers had some advantages over the first generation computers for e.g. 200 transistors are about the same size as one vacuum tube in a computer and also they were less expensive than a vaccum tube and also worked much faster.

Third Generation Computers: 

The introduction of integrated circuits (ICs), also know as chips opened the door for the development of third generation computers. A very large number of circuit elements (transistors, diodes, resistors, etc.,) could be integrated into a very small (less than 5mm square) surface of silicon and hence the name IC. The third generation computers used small-scale integrated circuits (SSI) which contain about 10-20 components. When large-scale integrated circuits (LSI) (around 30,000 components) were developed, the fourth generation computers were produced.

Fourth Generation Computers:

Fourth generation computers are also known as microprocessors. Microprocessor is a complete computer on a chip and can perform all functions of a computer like input, processing and output of data. They came into existence in the early 1970’s and are used until this day. With the introduction of these computers, computers became smaller, faster and more reliable and well as affordable.

 

Basic Components of a Computer:

 

Mainly, a computer is composed of seven parts:

 

1. Processor

2. Motherboard

3. Hard drive

4. Bus

5. Cards

6. Memory

7. Power Supply

8. Input Devices

9. Output Devices

 

Now, we’ll just briefly look at each component:

 

1. Processor:

 

Processor or CPU (as it’s commonly called) is actually the brains or the thinking part of a computer. This is the main chip that processes the data, executes instructions and generates the flow of data within a computer.

 

2.      Motherboard:

 

It is the main circuit board on which all the components are plugged in.

 

3.      Hard Drive:

 

Hard drive is the primary storage device where all the data is saved.

 

4.      Bus:

 

Bus is like a flat cable that contains a number of wires which are either on or off. These wires are like the roads which carry the traffic (or data) from one component of the computer to another. There are three types of buses present in a computer namely control bus, data bus and address bus.

 

 

5. Cards:

 

Cards are used to transport sound and video to your computer. They are hooked into the expansion slots of the mother board. Expansion slot is a slot on your motherboard which you can expand according to your needs, meaning you can add a number of cards for enhancing your computer’s performance like a sound or a video card etc.

 

 

6. Memory:

 

 Memory or RAM as its most commonly called is used to temporarily    store information in a computer. Once we close the computer, this  information is lost.

 

 

7. Power Supply:

 

A power supply is used for controlling and changing the household electricity that we use into one that a computer can use.

 

 

8.    Input Devices:

 

Input devices order the computer what to do. These devices include the mouse and the keyboard and can also include other devices like joysticks and game pads for gaming purposes. Input devices are the main way of interacting with the computer.

 

9.      Output Devices:

 

Once you have instructed your computer to perform a function (like surfing the web, writing a memo etc.) via your keyboard or other input device, the computer sends the results of that instruction to you through the output device, namely the monitor. Output devices tell us what the computer is actually doing. Printers and scanners are also output devices.

 

 

 

Other Hardware Accessories:

 

 

1. CD-ROM:

 

It is a high capacity storage device just like a hard drive but the only difference is that you can only read data from it but you can’t write to it. CD disks are inserted inside the CD-ROM slot for accessing data.

 

2. CD RW:

 

Nowadays, CD read/write drives are very common on which you can read as well as burn or write anything like software, music etc.

 

3. Printers:

 

It is a device that uses a special type of ink (commonly known as toner) to output the information from the computer by printing it onto a paper. There are many types of printers (ink jet, laser, dot matrix etc.) and they are all measured in terms of dpi (dots per inch) and ppm (pages per minute). The higher speed of dpi and ppm ensure the better quality of a printer.

 

4. Scanners:

 

Scanners are used to copy your printed photos and graphics and save them for display on a computer. They mostly use the graphic file formats like (.GIF or .JPG) for transforming the images into the computer.

 

5.      Web Cameras:

 

Web Cameras (or web cams) are used nowadays to send live pictures and videos to other computers. They are mostly used with a chatting software and once the camera is plugged on in front of you, the person chatting with you whether he’s sitting anywhere in the world, can see your live video on his computer monitor.

Sample exercise:

Now that you have learnt about some of the basic components of computers, I would like to divide the class into three or four small groups. Each group will pick one component of the computer like hard drive, memory, cpu etc. and then the group members will define the problems that they have faced regarding that particular component and what measures they took to solve that problem if any. I would like you to post your comments on the General Class Discussions page. Don't forget to mention the group name that you are in. I will myself distribute you in different groups and you'll be notified via email regarding which group you belong to and which component is selected for that group!

CD Rom Drives -

I have replaced the CD Drives on my PC twice.  It seems that the more I use them to burn and transfer data the more problems I have.

I am not sure if it manufacturing or frequent use that has been causing the problems.

What OS and CD burning software are you using? Are you getting any specific error or is it just the performance of your drive that has been degraded?

If it's in fact just a performance degradation issue then it might be that your drive has started operating in PIO mode instead of DMA mode. This problem occurs in Windows XP when the drives have been used to read discs that have errors on them. After about half a dozen of these read errors the drive controller reverts from DMA mode to PIO mode, which is the old and inefficient way of using them.

This is a simple problem to cure: all you need to do is to reset the operating mode to DMA rather than PIO.

Follow These Steps in WindowsXP:

 

1) Right click the My Computer icon on the desktop and click Properties.

2) Select the Hardware page and click the Device Manager button.

3) Locate the Primary and Secondary IDE Channels, and double click on the one your hard-drive is connected to (usually the Primary IDE Channel).

4) Open the Advanced Settings page on the IDE Channel Properties window that appears.

5) Click the Transfer Mode dropdown box and select "DMA if available".

6) Click on the OK button to confirm the changes.

7) That's it, you've just enabled DMA. Depending on the number of devices you have on your system, it could be useful to do this on the Secondary IDE Controller as well, and to both devices on each of them.

Alternatively, if you find your drive is locked in PIO mode it is simply a matter of uninstalling the appropriate controller in Device Manger by right clicking on it and selecting uninstall and then rebooting a couple of times and it will then have been reset to DMA mode. Most DVD drives are UDMA2 or simila

What Is Computer Troubleshooting?

 

Computer troubleshooting is the process of isolating the source of a problem and fixing it, typically through a process of elimination whereby possible sources of the problem are investigated and eliminated beginning with the most obvious or easiest problem to fix.

 

Mostly, the term troubleshoot  is usually used when the problem is suspected to be hardware-related. If the problem is known to be in software, the term debug  is more commonly used.

 

For this course, we will be applying the term computer troubleshooting to troubleshoot both hardware and software related problems.

 

The First Steps for Troubleshooting:

 

Before we move on to discussing computer errors and solving them, I would like to introduce you to the very basic steps of computer troubleshooting. These steps are the foundation for troubleshooting and reaching to the pit of a problem. Before we can start troubleshooting a problem, there are some important measures that we need to take in order to be successful in our troubleshooting. Just like before cooking something you need to have the ingredients or a recipe and plan at hand to create a dish, troubleshooting computer errors requires a little bit of planning as well. Here are some of the steps you will need to go through before unleashing your troubleshooting germs:

 

1. Just Relax:

 

Your computer has crashed or your monitor is showing the blue screen of death? What do you do? You panic. What you should really be doing at this point is relax. Yes, just relax, take a deep breath and simply move away from your computer for a little while. This is the first and foremost step towards good troubleshooting skills. You want to approach things in a systematic, calm, and controlled manner not when you are having a nervous breakdown! Panicking won't help solve your problem and it can only make matters worse. Just with any other life’s situation, panicking is never the solution to solving a problem. So remember, when faced with a problem all you have to do is relax!

 

2. Save the work ASAP:

 

After you have relaxed, the first thing you need to do is to save your current work (given that your computer is still on) so that you don’t lose anything valuable. Save it on anything like the hard drive, a floppy disk, cd-rom or a flash drive. 

 

3. Re-start the computer:

 

 When something goes wrong in your computer, your first best bet is to re-start the computer. Rebooting refreshes the computer as well as the memory and can also clear out the temporary problems. All you need to do is turn your computer off, wait for two or three minutes and then turn it on again.

 

4. Back up your important data:

 

When you feel that your hard drive is about to crash or the computer is having any kinds of problems, take preventive steps by backing up the important data while the computer is still up and running. If you always keep a full backup of your system, then you will only need to backup your recent documents. There are many ways to create a backup of your documents for e.g. copying the data either to a floppy, a separate hard drive, flash drive or a CD-ROM (if you have a CD writer installed on your computer). Most organizations do tape-backups for large amounts of data. Always remember that you shouldn’t wait for a thunderstorm to back your data up but you should always be prepared for a disaster by keeping a full backup of your system at all times.

 

5. Check to see if the cables and cards are fixed properly:

 

Cables running into and out of the computer sockets can easily get loose over time. Make sure they are tightly plugged in. You can also open your computer case to check all the connections and cables on your motherboard. After you are done checking your cables, look closely at the cards and memory slots inside the computer and give each of them a slight nudge to make sure they are properly fixed in their respective spaces. 

 

6. Ask yourself what you did last:

 

Sometimes, the computers start acting nasty on their own but there are those rare times when their acting weird is our doing. We can accidentally install wrong drivers or delete important system files that can cause the computer to crash or not work properly. So, once we have eliminated all the other basic possibilities, we should try to recall what we did last on our computer. Did we upgrade something or did we remove something? Maybe that can give us a possible solution to our problem. Another best way of preventing this problem is to create a system log file in which you can keep adding and tracking the changes that you make to your computer so in times of need you can consult that file. You can simply create it by right-clicking the mouse on the desktop and then choosing New(Text Document. When the icon appears, rename it to something like LogFile.txt or recentchanges.txt (anything that’s easy to remember). Next time you change something on your computer, just add an entry in that file. Your entries can be something like:

 

September 17: Updated the printer driver software Or

January 12: Deleted a file in My Documents Or

February 9: Downloaded a new screen saver

 

7. Make sure your hardware devices are working properly:

 

Wrongly installed hardware or hardware with no device drivers can cause a lot of problems too. Just right-click on My Computer, select Properties, click on the Hardware tab, and then click the Device Manager button. This will open the Device Manager dialog box. It lists all the hardware devices on your computer and the devices that have a problem will always have a yellow exclamation mark right next to them. Click on the problem devices and it will show you the details of the problem as well as some suggestions to fix the problem.

 

8. Check for viruses:

 

You should run a complete system scan with an anti-virus software like Norton or MacAfee but just make sure that you have updated the virus definitions; if not, you will probably get the notification and a link to log onto for updating the definitions and all you have to do is just follow the directions. You can also do a free online scan at TrendMicro's Web site at (). You should also scan your computer for adware, spyware, or other malware with a product like Ad-aware () or SpyBot Search and Destroy (). Just install these products and follow the instructions to run them.

 

9. Software and driver updates:

 

Always keep checking your hardware devices manufacturer’s websites from time to time as they might have introduced some updates to their products that can be useful for you. Software and hardware manufacturers these days often release patches or updates which include new codes to address the problems in their products and it is recommended that the purchasers download those updates and then run them on their systems as per the given instructions.

 

10. Getting online support:

 

Many manufacturers nowadays have support information for their products either on their websites or in searchable databases which are most commonly known as Knowledge Bases. They are basically a collection of similar types of problems collected in one place that many users have faced and then found a solution for. Also, there are a lot of tech-support discussion forums as well as technical support websites that provide online tech support for your computer problems. I also provide some online troubleshooting through my website at (). You can also reach Microsoft’s support page at .

 

 

Identifying Common Computer Problems:

 

This is a list of some of the most common computer problems that you have or will encounter as a computer user:

1. Computer or monitor doesn't turn on.

2. Blue Screen of Death.

3. Non System Disk or Invalid System Disk

4. Frozen Software.

5. Disappeared Icons.

6. Computer looks Dead

7. The keyboard isn't functioning.

8. The mouse isn't functioning.

9. The printer isn't functioning.

 

10. The computer starts in safe mode

 

11. Slow boot.

 

12. Weird Pop-ups.

 

13. Frozen Computer.

 

14. Computer restarts without a warning. 

 

15. Computer or CPU making weird noises.

 

16. No Sound.

 

17. Floppy Disk is not accessible.

 

18. Scanner isn't functioning.

 

In the next lesson, we are going to solve these problems one by one.

We are going to fix all the errors mentioned in the previous lesson by looking at the symptoms, diagnosing the problem and then finding a suitable solution. If you have ever gone to a doctor, you will easily understand this simple process!

1. Computer or Monitor Doesn't turn on:

Symptoms:

Computer or monitor's power switch is not responding when you press on it.

Diagnosis:

The computer or the monitor may not be plugged in properly.

Solution 1:

The first step to take is to check all the power cords. First take a visual inspection and then hold the side of the power cord that is attached at the back of the computer and then push it tightly into the power plug. Then verify that all the cords running from the computer to the power strip are firmly plugged into place. Sometimes, the cords may look properly plugged in but you have to push the cord into the plug physically to make sure it's not loose.

Solution 2:

Sometimes, when we have too many plugs attached on one power strip, it causes the power strip to surge. Therefore, try plugging the computer cord into a seperate outlet where no other plugs are attached.  

2. Blue Screen of Death:

Symptoms:

The software is behaving erraticaly or a program has either performed an illegal operation, caused an invalid page fault error, a fatal exception error or the "Dreaded Blue Screen of Death" (nothing shows on the monitor except a blue screen).

Diagnosis:

This either means a software failure or that the system has become unstable.

Solution:

The first step is to reboot your computer. First try to cancel all errors if the system allows you to and then restart the computer. If the window is stuck or for some other reason you can't reach the shutdown menu, then just push the power switch on your cpu directly and close the computer. Restart the computer again after about thirty seconds. Mostly, this takes care of the software errors.

Note: If errors still persist after frequent reboots then most probably there's a bigger issue going on and now would be a good idea to contact the computer manufacturer.

Tip: This is where a computer warranty comes into play. Whenever you buy a new computer, make sure you have at least a one year warranty which also comes with free technical support and service for your computer.

 

3. Non System Disk or Invalid System Disk:

Symptoms:

When you start your computer, it hangs up in the middle and gives you the above error.

Diagnosis:

Floppy disk has been left in the A: drive.

Solution:

Remove the floppy disk from the drive and just press any key. The reboot will continue without a problem.

Note: This is the most common error faced by computer users. People start panicking when they see this error. Don’t panic. Just look inside your floppy drive and eject the floppy out. Remember, a computer should never be booted while a floppy disk is inside the drive!

 

4. Frozen software:

Symptoms:

A program or software hangs up in the middle of something.

Diagnosis:

A software or program has become corrupt.

Solution:

When the software freezes, the best thing to do is to push the ctrl-alt-delete keys together. This way you can end the corrupt programs without having to restart the computer. After you press the "ctrl-alt-delete" key, simply click on the program name that you would like to end and then hit the "End Task" button.

Sometimes, the program will not end even after you press the "End Task" button and the same window will pop up again and again. If that happens, just relax and choose the "End Task" button again and the program will eventually end.  

Tip: Sometimes, even after hitting the End Task button for a lot of times, it will keep giving you the same error message or possibly a different error. If this happens, it is likely an internal error and is not going to go away just like that. To get rid of this error, just simply reboot your computer!

 

5. Disappeared Icons:

Symptoms:

When you log onto your computer, all your icons and shortcuts have suddenly disappeared from the desktop.

Diagnosis:

The  icons have not been loaded from HAL (Hardware Abstraction Layer).

Solution:

Simply restart the computer again and the icons will appear the next time.

6. Computer looks dead:

Symptoms:

The computer seems dead and you can't do anything in Windows.

Diagnosis:

The computer has either crashed or is processing some data that you have asked for it to process.

Solution 1:

Push the Num Lock key that is located right above the number 7 on the right-hand side of your keyboard. If you notice that the Num Lock light goes on and off as you tap on it, that means the computer is not locked up and is just busy doing what it's doing and all you need to do is to wait and give it some time to finish processing.

Solution 2:

If the Num Lock light doesn't light up when you press on it, then that's a clear indication that your computer has locked up. Just press the Ctrl-Alt-Delete twice or simply close the computer by pressing the power button.

7. The keyboard isn't functioning:

 

Symptoms:

When you turn your computer on and you get a message that no keyboard was detected or you get into Windows but are not able to type. 

Diagnosis:

The keyboard is not properly connected or it has gone bad.

Solution1:

Remove the keyboard connector for the CPU, examine the pins in the connector to ensure they are straight, and then reinsert the connector.  Also, check and make sure the mouse and keyboard connectors have not been switched.  If the keyboard still doesn’t work, try connecting another keyboard to the computer that you know is working.  This will determine if you need a new keyboard or if you have a CPU problem.

Solution 2: 

Press Ctrl + Alt + Del (all three keys at the same time) to bring up the Task List.  Select any program that says "Not responding" and click the End Task button.  Repeat until all tasks are ended.  Check periodically to see if the keyboard will work.

Solution 3: 

Check to make sure the keyboard is still properly connected to the computer.  If the keyboard has been disconnected, you may have to reboot your computer.

Solution 4:

If all else fails, then turn the power off.  Wait a couple of minutes before turning the computer back on.

Note: One of the dirtiest parts of your computer is the keyboard.  Regular cleaning will help keep the keyboard working properly.  First, blow compressed air through the spaces in between the keys to remove dust and lint.  If you shake your keyboard upside-down this will also remove some of the particles.

 

 8. The mouse isn't functioning:

Symptoms:

You cannot scroll around with the mouse or the mouse is working but you can’t scroll properly.

Diagnosis:

The mouse is not properly connected to the computer or it needs some cleaning.

Solution:

Check to make sure the mouse is still properly connected to the computer.  If the mouse has been disconnected, you may have to reboot your computer.

Tip: Like the keyboard, the mouse pad is sitting in the open most of the time getting dusty, wet, slimed, or anything else that happens on your desktop.  The mouse then rolls over whatever has collected on the mouse pad and gets inside the mouse.  To clean the mouse pad, wipe it off occasionally with a damp cloth or get a new one if possible (the mouse prices are really cheap these days).You should always clean your mouse regularly, as often as twice a week.  If you turn your mouse over, you’ll notice a round ball with a cover over it.  This cover can be twisted off and the ball will come out.  Roll the ball on a clean, lint free cloth.  Then take a look at the rollers inside the mouse.  Take tweezers, a screwdriver, or even your fingernail to scratch the dirt and lint off the rods.  Next, you should look inside the mouse and clean out any other dirt or lint that is hiding in there.  Finally, replace the ball and twist back on the cover.

 

9. The printer isn't functioning:

 

Symptoms:

The printer will not print. If this happens, then you need to determine if the printer itself will not work or if it is not receiving a print message from the computer.

Diagnosis:

The print cartridge needs to be replaced or there’s a problem in the printer itself.

Solution 1:

Make sure the printer is connected to the computer. After that, open the printer and see if your ink cartridge is finished. Replace it with a new one and then do a test print and see if that works or not.

Solution 2: 

Many models have a built-in self test option which allows you to print a test page by holding down the feed button for a few seconds.  The power button will begin to flash and a test page will print.  If the printer self test fails, your problem is with the printer itself rather than the printer cable or computer.

Solution 3: 

If the printer self test prints, the next step is to have Windows print a test page.  Click on Start, Settings, Printers, and right click on the icon of the printer with the problem.  Select properties and press the Print Test Page button.  If the test page fails to print, make sure the printer cable is firmly seated in both the computer and the printer.  You should also check the ends of the printer cable to make sure that none of the prongs are bent.  If the test print fails, or if the print consists of nonsense characters or a few characters printed over many pages, you need to uninstall then reinstall the drivers for your printer.

 Note: Paper feed problems and jams can often be resolved by using paper which confirms to the specifications provided by the printer manufacturer.  On ink jet printers, the rubber rolls which pick up each sheet can sometimes become coated with paper residue which decreases the friction.  Cleaning off the residue can sometimes solve paper feed problems.

If your ink jet printer is making a banging or grating noise, you need to clean two areas of the printer.

1.  Some models of ink jet printers have a gray colored narrow plastic film which extends almost the whole width of the printer just behind the rod on which the print head travels.  If this film gets dirty, the print heads can have problems determining where it is and can crash against the end of the printer.  Use tissue or soft cloth to clean this strip.

2.  The printer head moves across a rod that can also become dirty.  With the printer power on, raise the front of the printer and clean the rod with a paper towel.  Put the front of the printer back down and turn off the printer.  This time when you lift the front of the printer, the printer heads will move across the rod.  This will allow you to clean the part of the rod that was covered when you cleaned it the first time.  If you spray the paper towel with WD-40, this will do a better job of cleaning the rod. 

Tip: As the printer gets older, it may become necessary to perform these two cleaning jobs at least once a week.

 

10. The computer starts in safe mode:

 

Symptoms:

At times your computer could develop a problem which causes your machine to boot up in what is called "safe mode".  The easiest way to try and solve this problem is to run a "scandisk".

Diagnosis:

An error is causing the computer to start in safe mode.  

Solution:

1.  Click on Start, Programs, Accessories, System Tools, and Scandisk.

2.  Place a check on "Automatically fix errors".

3.  When Scandisk finishes, reboot your computer to see if this fixed the problem. 

4.  If the computer still boots up in the Safe Mode, click on Start, Programs, Accessories, System Tools, and Disk Defragmenter.  If you receive the message "You don't need to defragment this drive now", continue with the process anyway. 

5.  When Disk Defragmenter is finished, reboot your computer to see if this fixed the problem. 

 

11. Slow boot:

 

Symptoms:

 

Computer takes a long time to start up.

 

Diagnosis:

 

Too many applications are running in the background.

 

Solution:

 

1. Click "Start", then "Run".

2. In the "Open" field type "msconfig" and click "OK".

3. The utility that opens will have "Tabs" at the top. Click the one that reads "Startup".

4. You will see a list of all the programs that run when you start Windows. They will have check marks in the boxes to their left. We do not want them all to start.

Remove all the check marks (by clicking on them) except the ones beside "SystemTray" - ”Scan Registry" - "LoadPowerProfile" and "Task Monitor."  Also leave a check mark in anything that has the name of, or abbreviation of, your antivirus program or anything that looks like it might apply to "Norton" products.

5. Click "OK" at the bottom. You will be asked if you want to re-start your computer - do it.

 

 

Note: If, in the future, you notice things that you are used to loading when you boot up, but aren't - and that you want to load - then go back and check their boxes

 

 

 

12. Weird pop-ups:

 

Symptoms:

 

Ads and windows keep popping up while using the computer or while surfing the internet.

 

Diagnosis:

 

Your computer is infected with Adware.

 

Solution:

 

This is the most common infection of the internet age. This most likely means that your computer is infected with what is commonly called “spyware” or “adware”. These are unsolicited ads or pop-ups that travel to your computer via a tunnel created through the internet. These ads are used as tracking devices by various companies and advertising agencies as well as hackers. The authors of these applications include additional code that delivers the ads, which can be viewed through pop-up windows or through a bar that appears on a computer screen. To solve this annoyance, a number of software applications are available as freeware to help computer users search for and remove suspected spyware and adware programs.

 

I am listing two utilities along with links to download them. Download and run both of them on your computer:

 

1. Ad-aware:

 

2. Spybot - Search & Destroy:

 

 

Note: Download these utilities and follow the directions on the screen. If for some reason, the above links don’t work, you can always go to and type in the names of the utilities and then perform the download.

 

 

 

13. Frozen Computer:

 

Symptoms:

 

Computer is very slow or freezes while working.

 

Diagnosis:

 

Computer is low in resources or too many tasks are open at the same time.

 

Solution 1:

 

If you computer is very slow, you may have too many windows open. Check your task bar and close any screens that you no longer need.

 

Solution 2:

 

This can also happen if your computer has low resources for e.g. low memory or a small hard drive. If this is the case, then you should upgrade your memory and or increase your hard drive capacity.

 

Tip: To find out how much memory you have, right click on My Computer>Properties>General. On the bottom of the General tab you will see how much memory your computer has and other specifications like your processor speed etc.

 

 

 

14. Computer restarts without a warning:

 

Symptoms:

 

Computer keeps restarting by itself.

 

Diagnosis:

 

The computer is possibly infected by a virus.

 

Solution:

 

When this happens, it most likely means that your computer has a virus. There are several ways and software to remove a virus. Most computers today come with an anti-virus pre-installed that prevents your computer from being attacked by a virus. The most commonly used anti-virus software is called “Norton Antivirus” by Symantec Corporation. If you don’t have one you can buy or download one from the internet. Here’s the link:

 



 

Note: If you computer is actually hijacked by a deadly virus that cannot be removed by any anti-virus then you will probably have to remove the virus manually. You will either need to go to Microsoft’s website () for the removal tools or if you know the name of the virus (for e.g. Sasser worm, Trojan horse etc.) you can type it in a search engine (, etc.) and search the websites which offer steps to manually remove the virus.

 

 

 

15. Computer/ CPU making weird noises:

 

 

Symptoms:

 

Computer making loud, gurgling noises.

 

Diagnosis:

 

The CPU fan might have a problem. This is most commonly caused by over-heating of the computer. The noise actually comes from the CPU fan which has either stopped working or is in need of replacing. This can also happen due to the accumulation of dust inside the CPU.

 

Solution 1:

 

Remove the fan. Clean it along with the heat sink and then put it tightly back into place.

 

Solution 2:

 

If nothing works, you might look into replacing the fan.

 

 

Note: Sometimes, unfastened screws on the heat sink can also cause vibrations and noise.

 

 

16. No Sound:

 

Symptoms:

 

You can hear no sound while using the computer.

 

Diagnosis:

 

The speakers are not plugged in or the volume controls need to be adjusted.

 

Solution:

 

Make sure speakers are plugged into the surge strip and into the back of the CPU.

 

Also, double-click on volume controls in the system tray and make sure, the “Mute all” or “Mute” button is not checked.

 

Note: Sometimes, this is caused by a button on the speaker that is pressed off. Check if your speaker’s button is not accidentally hit off. Also, make sure the sound drivers are installed properly before taking the above mentioned steps.

 

 

 

17. Floppy disk is not accessible:

 

Symptoms:

 

When you try to access the floppy, you get the floppy is “not accessible” error message.

 

Diagnosis:

 

The floppy disk has gone bad.

 

Solution:

 

First of all, you should scan the disk for errors. Follow the following steps:

 

Go to Start>Programs>Accessories>System Tools>Scandisk

 

The Scandisk will fix your disk. Once the disk is fixed, IMMEDIATELY copy it by right clicking on the disk and then select Copy Disk. Now, Add copy onto new floppy.

 

The last step is taken to make sure you don’t’ loose your valuable information on the floppy. We will copy the data from the fixed floppy to a new floppy to create a backup.

 

Important Note: If you are using Windows XP, you will have to access ScanDisk from a different location. Follow the following steps:

 

1. Click on the Start menu

2. Select My Computer

3. Use the right mouse button to select the C drive. This will make a new menu appear.

4. Select Properties

5. Then select the tools tab.

6. Under the error checking select check now.

7. A new screen will show up, one is to automatically fix file system errors and the other is to scan for and detect problems with the hard drive. It is recommended that you select them both.

8. Click Start

9. You may be prompted to have Scandisk run when the computer is restarted, click YES when prompted

10. You may need to reboot your computer

Note: Scandisk takes a very long time to run, so be patient.

 

 

 

18. Scanner isn't functioning:

 

Symptoms:

 

You want to scan something and the scanner seems dead.

 

Diagnosis:

 

The scanner is either not connected properly or is not getting power.

 

Solution 1:

Verify cables connected properly to the back of the scanner

If the scanner is a parallel port scanner it is likely it has two available connections on the back of the scanner. Verify that the cable coming from the computer is connecting to the IN, Computer IN, computer, or similar connection.

Solution 2:

Ensure that the scanner is getting power

If your scanner is not getting power it is recommended that you check the connections ensuring that they are connected properly to the back of the computer and from the scanner to the wall. If you have the scanner connected to a power strip and or surge protector it is temporarily recommended that you connect the scanner directly to the wall.

If the computer scanner is getting power, you should notice the inside light come on when the power is first received by the scanner.

After checking the connections you still get no power to the scanner, it is recommended you contact the manufacturer of the scanner.

Solution 3:

Press CTRL + ALT + DEL and end task all currently running software except explorer and systray and attempt to scan again.  If this resolves your issue it's a possibility that an application in the background such as a virus utility is preventing your scanner from scanning.

Tip: Verify that the latest drivers are installed for the operating system being used on your computer. A listing of computer scanner manufacturers and links to the drivers pages can be found here: scanner drivers page.

In this lesson, we are going to discuss the most common error messages in Windows and how to solve them.

The Most Common Windows Error Messages

 

We are going to discuss the reasons behind some of the most common Windows error messages and will also find fixes for them.

 

1. Invalid Page Fault Error:

 

Reason: These types of errors mostly occur when the computers virtual memory gets a problem or becomes corrupted. Sometimes this error might also occur when some data is in use or is being changed by an application and some other application tries to access that data at the same time.

Fixing This Error:

If you frequently get the Invalid Page Fault in Kernel32.dll errors that means your windows password file might be corrupted. Mostly these errors occur in files like Explorer, Msgsrv32, Guide.exe, Commgr32 and others). Once you fix the password file, the error might be eliminated. Before you start to eliminate the file, just make sure that all your passwords are stored in a safe place because this procedure is likely to erase the passwords. Here’s how you do that:

• Select the \Windows folder from within Windows Explorer

• Press F3 to open the 'Find All Files' window

• In the 'Names' box, enter *.pwl

• Click 'Find Now'

• Delete all of the pwl files that are listed after the search completes

• Restart Windows

A Small Note about Virtual Memory: Most computers today around 128 to 256 MB of RAM that can be used by the CPU but most of the times that amount of RAM is not enough to handle simultaneous applications for instance if you are running an email program, a web browser and a word processor all at the same time. This is where Virtual memory comes into play. It looks for recently freed up spaces of RAM and then it copies those spaces onto the hard disk which in turn frees up space in the RAM for the other applications.

 

2. Fatal Exception Error:

Reason: This error is generated when an application that generated an error is not able to handle the error itself. When this happens, a fatal exception error occurs and normally the application that caused the error shuts down by itself but in some instances it causes Windows to shut down as well or makes it unstable. An example of this error can be an application in which the developer of the application might have used a wrong code.

Fixing This Error:

 

All you need to do to fix this error is to wait for the error to go away by itself. If the error doesn’t go away by itself or Windows becomes unstable, just reboot the computer and that’s it!

 

3. General Protection Fault Error:

Reason: This error is somewhat like the invalid page fault error. It mostly occurs when an application tries to use a block of memory that has already been given to another application. It can also occur if an application is low in memory or if certain system files are either missing or corrupt or you have installed a bad device driver.

Fixing This Error:

When an application tries to access or write to a block of space in RAM that is outside it’s designated storage area, the system will want the application to be closed and there’s nothing much that we can do about it except to restart the program and keep our fingers crossed, hoping it would run properly the next time.

If somehow the application does end up writing to a block of memory that is not it’s own, it would end up in overwriting other applications as well as operating system’s instructions that would eventually lead to a system crash. The only thing you could do at this point would be to immediately close down that application that’s causing the error and restart the computer.

Mostly a genereal protection fault error occurs if we are trying out a beta test-version software. However, this is not true all the time and even well-known applications can cause these errors as well. If you are constantly facing the same error then you should simply keep a check of the error messages, record them and then call the software manufacturer (the developer of that application) and ask them for guidance in resolving this problem.

A Small Note about Beta Test-Version Software: Any software that comes into the market always has to go through a ‘beta’ stage first. Simply put, it’s a testing stage that checks the software for errors and any other problems. Mostly developers are the ones who use the beta versions of software but nowadays, the beta versions are made available to general public as well through the software company’s website. They are mostly free to use but expire after a few days due to the same reason. If you ever see a ‘b’ in the version no. of an application that you download for e.g. (Version 1.3 b 4) that means it’s a beta version.

 

 4. Windows Protection Error

Reason: These errors mostly occur when there’s a damage to the registry, an unknown virus in the system, a hardware problem or some driver issues. This error mostly pops up when you start or shut down your system and it normally displays a message like, "While initializing device _Some-device-name_ Windows Protection Error". These errors can also occur when Windows loads or unloads a virtual device driver also known as VXD.

Fixing This Error:

 

There are many reasons and ways this error message is presented and many different fixes for it (depending on the type of error you are getting). Therefore, I am referring you to some websites which will show you how to solve these errors step by step.

 

1. Microsoft Website:

 



 

Click the above link and read all the articles regarding the Windows Protection Error and follow the solutions step by step. (Select the solution that best describes your situation.)

 

2. Error Messages for Windows Utility:

 



 

The above link is a free website where you can lookup any kinds of windows error messages by using their error codes (error codes are either number or a text based code that is normally generated along with the error). Click the link to download this utility on your computer by following the instructions on the screen.

Preventing Computer Problems     This lesson discuss the various steps and utilities that can be used to prevent any possible problems with our computers.

There are many computer problems that can be prevented right from the start if only we perform regular maintenance of our computers. It includes but is not limited to cleaning the computer, fine-tuning it and making it robust.

 

 

Following are some of the procedures that every computer owner should know how to perform. Once you are comfortable with each procedure, you will find you won't need to look into any notes or this lesson as a matter of fact! Keep experimenting with these procedures and your computer will forever be grateful to you.  

 

Always remember: practice makes a man perfect!

 

 

1. Basic Computer Cleaning:

 

The most common problem in the world of computers is either the slow performance of our systems or the nagging freeze ups that we face. The most common cause for freezing up of a computer is related to the unwanted accumulation of files that clutter our computer’s hard drive and in turn result in slower performance of the system. It doesn’t mean that all these files are created by our own hands, in fact most of these excess files are created simply while browsing the internet or using any other add-on programs. These files can be in the form of cookies or log events which most browsers today are capable of executing. Cleaning out these files routinely would keep your system up and running smoothly and will even improve it’s performance.

Carry out the following steps on a regular basis (at least once a week).

Delete Unwanted Files for Win9.x/Win95/Win98/Win2000:

1. Files left behind in your Windows\Temp folder:

Temporary files or “tmp” files as they are most commonly called are left behind when we shut down programs without closing them properly. For e.g. it can happen if you just directly shut down your computer by pushing the power button instead of closing it properly by going to Start > Shut down. When this happens you would normally get error messages or your system will freeze up in the middle of a task. There are some software and programs that place these temporary files in the Temp folders during installation. As a rule of thumb, they are supposed to be deleted once the installation finishes but mostly they don’t get deleted and keep residing in the Temp folder and accumulating extra space.

To erase these files, you should open your Win95/98/2000 Explorer or My Computer and then double click on the Windows folder and then double click on the Temp folder. Check to see if there are any important files that you have kept there. Apart from the files that you kept there, all other files should be deleted. You can do that by highlighting those files and folders, right clicking on them and then clicking on Delete.

 

If you receive a message saying "Access Denied," that means some program is using a tmp file. Just ignore it and delete the other files.

2. CHK Files:

After your computer is done performing a scan disk or fixing errors, it sometimes puts CHK files on your hard drive. You should delete these files easily by clicking Start > Find > Files or Folders and then typing in *.chk and clicking on Find now. Once you see all the CHK files, delete all of them.

 

Delete Unwanted Files for WinXP:

1. TMP files:

In Windows XP, you can remove the TMP files by doing these steps:

Just open Windows XP Explorer or My Computer then click on C: and then click on the Windows folder and then right click on the Temp folder and finally click on Delete.

2. CHK Files:

To remove CHK files for Windows XP, follow these steps:

 1. Click Start button>Search>All Files and Folders and then type this:

*.tmp, *.abi,*.chk

2. Click on Search.

3. Once you get to the result window do this:

Delete all the chk files that you find. Highlight the files, right click them and then click Delete.

Delete all the tmp and abi files located in the 

Note: Once you have removed all these tmp and CHK files from your computer it is strongly recommended that you perform a system scan by Scandisk and defragment your hard drive as well. Scandisk and Defrag are utilities that correct problems and close the gaps between all data on your hard drive so that it can be read correctly.

 

 

2. Scandisk and Defrag for Windows 95, 98, ME, 2000

ScanDisk and Defragmenter are used when your system is running slower than usual or you keep on getting Windows error messages. These are built-in utilities in Windows and are readily accessible. The main function of ScanDisk is to check your drive for any errors and the main function of Defragmenter is to arrange file data efficiently by filling in all the gaps so it can be readily accessible. But before you run these utilities, there are a few steps that you need to perform:

1.      Close all the applications that are currently running.

2.      Make sure no programs are running in the background. Press CTRL + ALT + DEL to open the Close Programs list. Highlight each program except for Explorer and Systray and click on End Task.

3.      After that, empty your Recycle Bin. Right-click on the Recycle Bin on your desktop and then click on Empty Recycle Bin.

4.      Now give your system some time while its performing the defrag or ScanDisk and don’t open up any programs while system is in the process of doing that.

ScanDisk:

 Always run ScanDisk before you run the Disk Defragmenter. Here’s how you would run ScanDisk:

1. On your Taskbar, click the START button, then click Programs > Accessories > System Tools > ScanDisk.

2. Select the drive you want to scan, mostly it’s (C:). If you are running programs on other drives, you may need to scan more than one drive. For Type of Test, select Standard, and put a check in the Automatically Fix Errors box.

3. Click Start and wait for the process to finish.

 

 Defragmenter:

Defragmenter brings together fragmented files (any time you load or delete a file or program, it leaves empty spots on the hard drive which are known as fragmented files) and folders on your computer's hard disk, so that each occupies a single, contiguous space on the volume and the hard drive reads the information faster. This in turn, frees up more space on the hard drive as well making it less likely for new files to be fragmented in the future.

1. On your Taskbar, click on the START button, then click Programs > Accessories > System Tools > Disk Defragmenter.

2. You will be asked to select a drive, select your C: drive, then click OK. Sometimes you may get a message saying that you don’t need to defragment your drive at this time, but check to see if the drive is more than 1% defragmented. If it is, then you should run Defragmenter anyway. Also, if your hard drive is partitioned, you should perform this operation for all drives.

NOTES Win 98/Win ME:

For Windows 98 and ME you should, Click the Start>Settings button, and then make sure Check the drive for errors is selected. If you choose "Rearrange program files so my programs start faster," defrag will take longer to complete. That option isn't necessary each time you use the Defragmenter.

NOTES FOR Win95:

After you enter the Disk Defragmenter utility, make sure you also click the Advanced button and then select Full Defragmentation. Again, make sure the Check drive for errors is selected and also select Save these options and use them every time. After that, click OK.

Once the defragmenter is finished doing it’s job, just restart the computer.

 

 

ScanDisk/ Defrag for Windows XP:

 

ScanDisk:

For Windows XP follow the following steps to perform ScanDisk:

1. Double click on My Computer on your Windows Desktop

2. Highlight and right click on your C drive then click Properties, then click Tools tab.

3. When you see "Error-Checking" click the Check Now button and put a check in the Automatically Fix Errors box.

Note: If you receive an error message stating: "The disk check could not be performed because the disk check utility needs exclusive access to some Windows files on the disk. These files can be accessed only by restarting Windows. Do you want to schedule this disk check utility to occur the next time you restart the computer?" just click the YES button and reboot the computer.

 

 

Defragmenter:

 

1. Go to Taskbar and click on START button, then click All Programs, then Accessories, then System Tools, then Disk Defragmenter icon.

2. Under the category "Volume" select C: drive and then click on Defragment.

When Defragmenter is complete, restart your computer.

 

 

 

3. Cleaning the Windows Registry:

 

Windows Registry Cleaning for Win 95/98/ME/2000:

Sometimes when we install and uninstall certain programs, certain registry keys are either modified, added or deleted. Over time the registry might start getting filled with these unused files especially if you don’t manually remove these keys after you uninstall a program. This results in slower access to the registry which in turn slows down the computer’s performance as well. There is a utility created by Microsoft, that cleans up these unwanted registry entries. The program is readily available for download and can be downloaded by the following link. Just copy and past the link into your browser and follow the directions for downloading this program called RegClean 4.1a:



After you are done downloading the application, just click on Start on the task bar and then click on Find > Files and Folders and then type in “regc1n41.exe” and click on Find Now. Once you see the regc1n41.exe file just click on it to start it’s installation. Once the installation is finished, you will get a README.TXT file in the folder where you have installed the application which will guide you on how to run the utility and clean your registry.

Even after performing all these steps, if you still have a slow computer performance problem, then try these tricks out:

For Windows 9x, ME, 2K, XP:

You should always have all the updated programs. For that, you need to access Microsoft Windows Update. Go to this website by clicking on the link and then click on Product Updates. Wait for it to process the information and make sure you get the “critical” and “recommended” updates for your version of Windows. Running these updates can also greatly enhance the performance of your system.

 

 

4.Disabling StartUp programs in Win 98/ME/XP:

 

One easy way of enhancing your computers performance is by disabling certain startup programs that run every time you log on to the computer and do nothing but slow down your computer’s performance by taking unnecessary space. You can disable these programs by taking the following steps:

 

1. Click Start >Run. Then type MSCONFIG and then click Ok.

2. Click on the StartUp tab.

3. When you see a list of tons of programs, just uncheck all of those programs except for these: Task Monitor, Registry Scan and Systray.

4. Now restart your computer and see how it works.

 

Note: You can always go back MSCONFIG to re-launch the programs that you have disabled if at anytime you feel that they should be running at startup.

 

To completely prevent those programs that you have disabled from running at startup again and again you will have to edit the Win.Ini file. Follow these steps.

 

1. Click on Start > Run and then type SYSEDIT and then click on Ok.

2. Then click on the C:\WINDOWS\WIN.INI tab.

3. Look at the top for a name called [Windows]. In that section, look for the load= and run= lines. If those lines are empty, just close the System Configuration window. If there is anything in those lines, put a semi-colon in front of the line, so it would look like this:

;run=c:\etc

;load=c:\etc

This will prevent the programs from loading up at startup.

 

Note: If you remove the semi-colon, the programs will again start loading at startup.

 

 

Disabling StartUp programs in Win 95:

 

For Windows 95, you should simply hit CTRL+ALT+DEL at the same time and this will bring up a Close Program list. Just disable most of the programs that are running but keep the Systray intact. Follow these steps:

 

1. Right click on the Start button and then click on Open.

2. Click open the Programs folder and then double click the StartUp folder.

3. Select all the items in that folder and hit the Delete key.

4. Restart your computer.

 

To completely prevent those programs that you have disabled from running at startup again and again you will have to edit the Win.Ini file just as you did in the previous section. Follow these steps.

 

1. Click on Start > Run and then type SYSEDIT and then click on Ok.

2. Then click on the C:\WINDOWS\WIN.INI tab.

      3.   Look at the top for a name called [Windows]. In that section, look for the load=      and run= lines. If those lines are empty, just close the System Configuration window but if there is anything in those lines, put a semi-colon in front of the line, so it would look like this:

;run=c:\etc

;load=c:\etc

 

 This will prevent the programs from loading up at startup.

 

5. Disk Cleanup:

 

 

There is a utility in Windows called Disk Cleanup that takes care of your unneeded files by cleaning them out. A lot of computer usage especially internet surfing can easily fill our hard drives with innumerable junk files that do nothing but sit on the hard drive and slow down the computer’s performance. To access the Disk Cleanup utility, just click on Start > Programs > Accessories > System Tools > Disk Cleanup. First select a drive for e.g. C: and then click on OK. After this, you’ll see a list of different files that you can remove. Just select the files that you want to delete and click OK. You’ll also be provided with an explanation for each file by Windows. You can also look under the More Options tab for more choices. Also, repeat this process for all the drives in your system.

 

6. Emptying the Recycle bin:

 

 

Just throwing garbage in a garbage can doesn’t take it away, you have to empty the garbage can so that it’s picked up and taken away. The Recycle Bin in Windows works the same way. Just by emptying the unneeded files and programs into the recycle bin doesn’t mean that are deleted from the system, you have to actually empty the recycle bin itself. The files sitting inside the recycle bin are always taking space on the hard drive that can also degrade the performance of your computer. To empty the recycle bin, take any of the following steps:

 

1. Right-click on the Recycle Bin and then click on Empty Recycle Bin.

2. Double-click on the Recycle Bin and then press Ctrl-A to select all items and then press the Delete key.

3. Double-click the Recycle Bin and then select all the items at once and then right-click on them and select Delete.

 

 

Using Add/Remove Programs: Removing Orphan Files:

 

 

Whenever we install a new program it comes with hundreds of files some of which are actually used by the program but some of them are used for creating unnecessary shortcuts, icons, shortcuts on your start menu and some of them can even rewrite your system files. If you go delete these unwanted files by just clicking on them and deleting everything in sight, you are actually leaving all these files behind because these files don’t get deleted so easily. The most efficient way of doing this is to use the uninstall file that most of the programs today come with but if the program didn’t come with an uninstall file, then you can remove the software or files by using the ‘Add/Remove” option under the control panel of your operating system. To access it simply follow these steps:

 

Click on Start>Settings>Control Panel>Add/Remove programs and then click on the program that you want to install or uninstall from the list of given programs and simply follow the instructions.

 

 

 

 

6. Deleting Cookies:

 

Cookie is like a unique identifier that is placed on the hard drive of your computer every time you browse the internet. Cookies are in fact small pieces of text that are generated by web servers and they are used to allow organizations to store the information on the user’s machine and later retrieve it. They are mostly used for beneficial reasons but can sometimes be used in terms of marketing and advertising purposes. They can sometimes accumulate a lot of hard drive space and result in slowing the peroformance of the computer. To delete these cookie files, follow these directions:

1.      Start Internet Explorer.

2. On the Tools menu, click Internet Options, and then click the General tab.

3.      In the Temporary Internet Files section, click Delete Cookies, click OK, and then click OK again

 

 

Assignment: Run all the utilities on your computers by performing the steps mentioned above. After that, make a note of how your computer is performing. I can bet that you’ll notice an increase in performance in your computer!

H

ow to Format and Install an Operating System   Programs>Accessories>Command Prompt or simply by going to Start>Run and then typing cmd and hitting enter).

 

4. Once you are in DOS prompt, type in: SYS A:

 

5. Now exit your DOS prompt and go to your Start Menu and then go to FIND then FILES OR FOLDERS.

 

6. Now you need to search for the following items:

    a)

    b) FDISK.EXE

 

Type both of these file names one by one and each time the files appear in your search window, right click on them and then select the "SEND TO" option and then "send to" your 3 ¼ floppy drive icon. Once both these files are copied to your floppy, you are all set to boot up your computer again. Make sure your BIOS is set to read your floppy drive first for the boot up sequence (most operating systems are configured for that already so you don't have to worry about that, but if you suspect that your system is not configured for that you'll have to log on to your BIOS. If you don't know how to do that you can consult me).

 

Now simply shut down your system, insert your floppy and turn the power on once again. Wait for everything to start up and then you'll find yourself at a DOS prompt window, which will look like this:

 

A:>

 

Now, you need to type in FDISK.EXE. This command will start the program that will prepare your hard drive or drives for formatting. The program is fairly easy and all you have to do is follow the instructions. It might give you an option to enable large hard drives and if it does, I recommend that you take that option as it saves you the hassle of having to split up your large hard drive into smaller partitions.

 

Once FDISK is finished, you will need to reboot your computer again. Make sure that you keep your floppy disk or the system disk intact inside the system. Once again after rebooting, you'll find yourself at a A;> DOS prompt which will be more colorful. Now you are all set to format your hard drive. Simply type:

FORMAT /S C

This will format your hard drive and then you'll have to reboot the system again. But this time, make sure that you have taken the system disk out of your computer. After rebooting, if all went well, you'll see a C:> prompt. Now the next thing you will want to do is install your CD-ROM for DOS. Refer to your CD-ROM instructions for this. You will need to reboot once again, but that will be one of your last times. After you have rebooted, and you are once again at the C:> prompt, insert your Windows 95/98 CD-ROM into the CD-ROM drive and then type:

D:> SETUP.EXE (replace the D: with the appropriate drive letter of your CD-ROM).

 

Now, if the Windows setup starts up, then you are all set and all you have to do now is to follow the instructions as Windows will take over the installation form this point and prompt for all necessary inputs. The rest is real easy stuff!

 

It will take some time for the whole installation process, so just relax, take a break and come and look at your installation progress from time to time.

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