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When I fresh boot my computer everything is dandy. Then after a few hours applications like Visual Studio, Notepad++, Games, iTunes, Windows components (Cmd prompt, Explorer, etc.), etc. stop working with errors about missing files or not being installed correctly.
I found that if I browse out to Cmd.exe and run it directly (instead of from the menu link) then I can run it, and the WinDir environment variable and others are missing (which explains why I can't run Cmd.exe from the shortcut since it uses %WinDir%\System32 for the path) and the system path is set to (NULL).
When I go to Advanced System Settings (again manually exploring to SystemPropertiesAdvanced.exe) all the environment variables are still there. I checked my memory utilization and I have 1 of 6 Gig free, with my Commit Charge peak well bellow the limit (like 30%).
The clipboard also stops working too.
Not running anything to exotic, although I do have a lot of Chrome tabs open. Running Backblaze for backup, Microsoft Security Essentials, and various other utilities. Closing things one at a time hasn't seemed to fix it.
It has been getting progressively worse (happening sooner and sooner). Would like to know what is causing it without reinstalling.
Running Windows 7 Ultimate 64-Bit