Trouble Opening winmail.dat Files

Tip suggested by Donna Swartz, Business Office, and Karen Struble, Development.

Someone keeps sending me winmail.dat files that I can't open. What are they? What can I do? Hmm... Let's answer these questions one at a time.

What is winmail.dat?

A winmail.dat is the file Microsoft Outlook generates when an Outlook message is sent in Rich Text Format or as HTML mail. In other words, if the sender of the message is on Outlook and uses anything other than plain text—things like colors, fonts, italics, etc.—the message will be send as a winmail.dat attachment.

For other Outlook users, this is not a problem. Their email clients can open the message and view it exactly as they composed it. However, many other clients are unable to open this message. Depending on the options they have selected on send, they either get a plain text message plus the attachment they cannot open or—worse yet—no message at all, just the attachment.

What can I do?

If you receive a winmail.dat file and cannot open it, you probably want to know what your options are. Your best option is to contact the sender and ask him/her to send the message as plain text (usually found somewhere under Outlook's Tools→Options menu).
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