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

What is the deal with those winmail. dat files? I get them in my email all the time, and nothing seems to be able to open them.

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 ...