Possible quartz.dll access violation solution
 

Hey I just thought I'd leave a note here so someone can confirm this, or maybe it will help someone else with the same problem.
I was getting errors in BSPlayer on every video I played on a Vista SP1 system for the last few days, while it was working fine before, and no other media players were affected. I tried many things to fix it but I couldn't do a system restore back far enough thanks to some rootkit and I assumed it was some registry corruption causing this. I finally got it fixed though, and it turns out all I had to do was disable the setting "enable DEP (Data Execution Prevention) for all programs" under windows control panel, system properties, advanced, performance settings. Windows is supposed to just close programs that violate this after notifying you, but I guess it's able to crash things too :(