A free and open source (GPLv3) Android app Opener – A free Android app Reader - Free Android app also available Online winmail.dat extractor and document converter – Free, in modern, responsive theme Reader Online – The online version of the Winmail.dat Reader (free) tud.at service – Web service and GPL licensed PHP script for reading attachments in winmail.dat files www.winmaildat.com – Another online winmail.dat extractor which allows to upload up to 5 MB the-computer-site.com – converts winmail.dat file to a zip file Software libraries JTNEF – GPL Java TNEF package POI-HMEF – Java library of the Apache POI project MVCOM – Commercial COM component to parse TNEF Convert::TNEF – TNEF library written in Perl tnefparse library – TNEF access library written in Python, licensed under LGPL Aspose Email – Commercial Java and .NET library that can parse and extract TNEF data EAGetMail Component – Commercial .NET and ActiveX library that can parse and extract TNEF data node-tnef - NodeJS command line tool/library that can parse and extract TNEF data libytnef – GPL TNEF extractor library written in C MimeKit – A .NET MIME creation and parser library with support for TNEF References External links Specification: "M-OXTNEF: Transport Neutral Encapsulation Format (TNEF) Data Algorithm" - MS-TNEF format specifications Microsoft Support: "How e-mail message formats affect Internet e-mails in Outlook" - How to disable TNEF in Outlook 2002 and 2003 "Description of Transport Neutral Encapsulation Format (TNEF) in Outlook 2000" - How to disable TNEF in Outlook 2000 "How to configure Internet e-mail message formats at the user and the domain levels in Exchange Server 2003" - Includes instructions on disabling TNEF Other: "Microsoft Outlook MS-TNEF handling (aka Winmail.dat or 'Part 1.2' problem of unopenable email attachments)" Windows communication and services Microsoft Office Email