Whenever I attempt to log into a Windows Vista computer (the only account on it), I'm presented with a black screen & a cursor.

I can open Task Manager, and from there I can launch applications.

It seems to be using Aero Basic (instead of the full Aero which I had set as default before the problem started).

When attempting to launch "explorer.exe" I get "explorer.exe - Application Error 'The application failed to initialize properly (0xc0000022). Click OK to terminate the application.'"

Every now and then I get an error along the lines of "the application has failed to start because its side by side configuration is incorrect please see the application event log for more detail."

I can boot into safe mode successfully, but I still get the black screen when I log into it in regular mode. I've tried most of the suggestions here, but did not work.

I'm attempting to back up everything right now in case the only fix is to reinstall Windows. Has anyone seen this before?