Microsoft Office 2000 Resource Kit ReadMe.doc

Excel 4 – High Security and .xlm add-ins. If you plan on using Excel 4 style macros (.xlm) you will need to add a registry entry to enable their use if you also plan on using High Security. Excle .xlm macros cannot be digitally signed and cannot load when High Security is enabled. Some Excel add-ins were created using .xlm. ................
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