How to get that all-important piece of software working on Windows has vexed Microsoft since the beginning of the operating system. Compatibility was king.

Things were simpler in the days of Windows 3.1. It was up to the user to tell the system which application was which in the event they shared a filename. Veteran Microsoft engineer Raymond Chen gave the example of C:\MAIL\MAIL.EXE. Perhaps it was Microsoft Mail? Or maybe it was cc:Mail for MS-DOS?

The APPS.INF told Windows what to do with the application, but it was up to the user to differentiate apps that shared the same filename. Simpler times indeed.