I had Windows 7 installed in one drive. Then I installed Windows XP on the other drive. I was installing the software and everything was working fine on my desktop PC.
Suddenly my resolution changed and what I see the desktop and programs which were installed on Windows 7. The Windows is XP but all programs automatically changed to which were installed on Windows 7
EDIT: When I installed XP then I was installed all software in it. While everything was ok, I was installing WinRar. Then suddenly screen got blackout. Then when screen came back after 5 seconds. Then I lost my graphics card driver. All icon become big and I saw that all icons on my desktop was from Windows 7 desktop. I checked my program list and all programs were from Windows 7 which I installed in Windows 7. I don't know how got swapped.