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I'd like to know how Windows XP, Vista and 7 handle files without a file extension. I'd test it myself, but I don't have access to a Windows machine currently.

To my knowledge, Windows XP throws up over files with no extension, while Windows Vista an 7 are still incapable of reading the magic bytes to discern the MIME type, so the file is opened with the correct extension. Am I correct, or does Windows handle MIME types properly now?

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up vote 3 down vote accepted

Windows Vista and Windows 7 throw up the following window upon opening a file with no extension when you double click a file:

enter image description here

There is no checking done within the file (I tried a renamed PDF) and on a system that fully expects files to have an extension for it to work properly I would doubt mime-types to work anywhere outside of a web-browser.

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Mime types work fine on Linux. Not sure about Macs, but I'd imagine they do too considering they're POSIX compatible and are very close to Linux (BSD). Silly, silly Windows. Thank you for testing this out for me. – Bojangles Sep 18 '11 at 12:55

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