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SiliSoftware » Tools » WINMAIL.DAT TNEF decoder

WINMAIL.DAT to usable files decoder

Microsoft Outlook defaults to a proprietary encoding format called Transport Neutral Encapsulation Format (TNEF) which no other email program can decode (not even Outlook Express). Users of other email programs will get the plain-text version of the email, and a mysterious attachment called winmail.dat which cannot be opened by anything. But if you upload your winmail.dat here, you will get a gzip version with the actual attachment(s) inside.
Upload your WINMAIL.DAT: (max 2,097,152 bytes)

Actual decoding is done by the open-source program TNEF (this page is simply a front-end for it).