I got tired of having to click on the Startup Programs icon everytime to
enable such basic things as my Anti Virus scanner so I decided to disable
UAC. I'm not sure why Vista won't just automatically allow a program to
startup even though I've manually asked it to many times but that's a
different matter.

After disabling UAC I noticed that my programs seemed to have reverted back
to an older state. I backup all my Trillian chat logs and after I turned off
UAC all the new data were gone. The logs had reverted back to my backups
right before I had installed Vista. All my conversations that happened after
I installed Vista were gone. I checked the actual files in the Trillian
folder and it had been rolled back as well. Re-enabling UAC returned the
logs back to the state they were in before I disabled UAC.

I noticed the same thing with other programs as well. Feedreader marked
news items that I have previously read as unread. Again, after re enabling
UAC the items were correctly marked read again.

Winamp also didn't have the same play list and media library, it was back to
an older state.

Why are program data not being saved properly?