Right click on Computer,
click Properties,
click either Advanced Tab or Advanced System Settings (varies with Windows version)
Environment Variables should have a button near the bottom.
If it is blank you should be able to find example path,comspec and extended path strings on google. My system path includes:
%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;%SYSTEMROOT%\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\ATI Technologies\ATI.ACE\Core-Static
I have a 64 bit system. If yours is 32 bit you won't have C:\Program Files (x86) it will just say C:\Program Files
Edit: If you have W7 see this
http://www.sevenforu...iations-restore.html