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.