Sorry, forgot to clarify...

I'm not talking about programs that get run after Windows starts. I know all the places where a program can get run. I'm talking about the built-in windows mechanism for replacing files before Windows starts, before it hits the Run keys, before the Load= and Run= sections of Win.ini, before the StartUp group. Before even the Windows GUI loads.

In Windows 95/98, this is the place where you sometimes see the text "Finished updating files, continuing to load Windows" appear. Of course, in that case, it's using WININIT.INI, because that message never appears in NT-based operating systems.

They replaced the functionality of WININIT.INI when they did NT 4.0 and later, there's something it's doing that's pretty much the same thing, and it doesn't have to run a third-party program to get the job done, it's built in to Windows. I just don't know where it is exactly.