Microsoft

2.2.5 [RFC2445] Section 3.10 File Extensions. V0005: The specification describes the .ics and .ifb file extensions. Exchange 2007, Exchange 2010. Exchange can export files with the .ics file extension, but does not export files with the .ifb file extension. Exchange does not import files with the .ics or .ifb file extensions. V0006: ................
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