qttask.exe is part of Apple's QuickTime media player and also (I believe) part of iTunes. It launches at every boot so as to make playing Quicktime media slightly faster. For some reason, qttask.exe is doing something that makes Windows think it should disable the desktop effects. This type of behavior is more commonly found in older software written before Windows Vista was released. If your version of QuickTime (or iTunes) is that old, it is rather important for you to install the latest version for security and stability reasons.
If you have the latest version already, or if updating doesn't fix the problem, you can simply remove the qttask.exe entry from your system's start up sequence. This won't have any negative effects on QuickTime, iTunes, or your system. You can use the built-in MSConfig tool
to disable the qttask start up entry:
Edited by Andrew, 22 November 2011 - 02:01 PM.