LookOut is a plugin which allows Thunderbird to interface with Microsoft’s mail tools by decoding metadata and attachments encapsulated/embedded in a TNEF encoded attachment (aka winmail.dat).
The TNEF decoding engine was inspired (with permission) by the tnef.sf.net project. LookOut has a full MAPI decoder and the ability to transcode some of those properties to iCalendar (ics) and vCard (vcf) formats. As an option all MAPI properties within a email can be viewed so other types of information can be deciphered.
If you’re a Mozilla Thunderbird (or Seamonkey) user and you’ve got enough of your email’s inbox full of those dull attachments install this LookOut plugin without hesitation, you’ll finally see those files as the sender’ meant you to see.