Long before automatic updates, the Windows 95 team tweaked third-party software to keep it running

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.

Windows 95, however, dialed things up quite a bit with its application compatibility database. The behavior of the operating system could be altered based on compatibility flags, and Microsoft went so far as to automatically patch programs where a simple ...