Though DAT files, which house data as the shortened name implies, are usually best left alone, here's how you can open them.

Change Association This Time 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.

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 ...

Q. I sometimes receive e-mail messages with a “winmail.dat” file attached that I cannot open. Why does this happen, and what can I do to fix it? A. The winmail.dat file usually appears because ...