Letter Opener converts winmail.dat attachments on the fly, so you can actually see and use the attachments the sender intended you to have. [Editor’s note: The following review is part of Macworld’s ...

If you live in a world where you get email from Outlook users, and I think most of us do, you probably see the dreaded winmail.dat file on occasion. Outlook compresses all of its attachments together ...

Many times when receiving mail attachments with the new Exchange-enabled Microsoft Entourage v.X from Windows users, you will get a winmail.dat file that is inaccessible under Mac OS X. Alan Sill ...

However, things changed with Windows 11/10/8. In Windows 11/10/8, Index.dat files are not used by Internet Explorer 10. The indexing functions are being implemented within a Microsoft database system.