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 straightforward ...

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 various ...