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

To make Notepad files always open in a new or separate window in Windows 11, open Notepad setting and change the 'Opening files' option.

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 ...