Windows cannot find c:\windows\system32\notepad.exe --issue after playing with replacing notepad by notepad++

1. open windows registry editor (as administrator)
2. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options
3. remove (if exists) notepad.exe

http://superuser.com/questions/95957/windows-cannot-find-c-windows-system32-notepad-exe