If your e-mail client is not set to support the Microsoft Outlook rich text format, you might receive an e-mail message that carries a "winmail.DAT" attachment, due to the fact that mail programs handle file formats differently.
In order to view the hidden content of these attachments, you could instruct the sender to change Outlook's settings or use an application that can read them. Such a program is Winmail Opener, a lightweight utility that can “translate” TNEF encoded messages.
Simple GUI with support for “drag and drop”
As all it does is decrypt the .DAT file, the interface only comprises two panes, one for the message body and one for the attachments. In order to open a new winmail.DAT file, you can use the default PC browser or just drop it in the main window of the program.
View information, save it to the HDD and use a command console
Once the DAT file is selected, you can view the detailed information embedded into the TNEF file, such as the mail subject, sender and the message content, which can then be saved in an RTF format to a custom location. Also, the detected attachments can be dragged and dropped to any location in order to save them to your PC.
The software can also be run using the command console, where you can process multiple encoded messages at the same time or even decode a file and save its attachments without viewing it.
Evaluation and conclusion
Designed with simplicity in mind, this multi-lingual application is very easy to use, which makes it suitable for any type of user. If your e-mail program is not set or cannot read the Outlook formatting instructions, Winmail Opener can do the trick. It really comes in handy if you are looking for a fast solution to opening encoded Outlook DAT attachments.
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