Dave, there are a couple of people who send me email, and, consistently, their attachments don’t show up as neat “foo.doc” or “report.xls” but as the generic attachment winmail.dat. They don’t know why and I don’t know why. Worse, as a Mac user, I can’t figure out what to do with them. What’s causing these “winmail.dat” files and how do I decode ‘em?

I too have variously been plagued with this winmail.dat affliction, and as far as I can tell, the problem is that Microsoft Exchange servers use the mysterious winmail.dat method of encoding attachments that are sent from one Microsoft Outlook user to another through a Microsoft Exchange server.

Of course, you clearly aren’t using Microsoft Outlook for Windows (since it would have magically decoded the attachment, leaving you none the wiser), and are instead faced with trying to decode this mysterious attachment…

Again, from what I’ve read, the real fix is…

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