Vista 64bit Start menu items are not executing

For a change I decided to give this os (Vista Home Premium 64bit SP1) a
chance and not curse the system and reboot, but try to diagnose the
problem.

Well the problem is as it is stated in the title. I can run all desktop
items, but for some reason nothing in start menu works. Everything was
working fine until one 3rd party application crashed to desktop 3 times
in about 1,5 hours. (Not) suprisingly vista was unable to find the
cause. My previous experience would say that this could be related to
faulty hardware drivers but vista says that they are the latest.

Now since I want to find the cause and maybe even fix it I wonder what
ways or tools should I use to get to the bottom of this?


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