If you're having trouble opening a DAT file, I'll show you a simple and free way to do it. This method works on both Mac and PC. Just open your browser and go to winmaildat.com. It's a ...

Tips on opening a winmail.dat file, keeping seldom-used ink cartridges from drying out, and undoing an Undo.

Sometimes you may want to open a data file with a different program. To open a file by choosing the application, see Win Open With. Change Association Permanently.

Q. I received e-mail from a relative that says it is in a winmail.dat file. When I try to open the file, I get a message that says something like: "You are attempting to open a dat file. They are ...

Every data file on your PC should be associated with an application, so that opening the file will open the right program. But the official "right" program isn't always the right one for you.

If you can’t convince the sender to use standard email formats, you also have a few options for reading these Winmail.dat-formatted messages. On the Mac, TNEF’s Enough, can open winmail.dat files.