Help needed with virtual pc 6! plz....


I'm having troubles with virtual pc 6. I've installed it put it into applications and documents for the windows 2000. But when its all installed and i open virtual pc 6 and click on the windows 2000 window in the list it sez " os not found, install an os on the hard drive" but havnt i done this?? cos i did copy it to the apps and the docs for window 2000. it should run right???? plzz help me out people..
When i open the control panel where you have the list of pc users like nt, 2000, me, xp etc i click on 2000 and it dosnt seem to work? dosnt open, well it does but all i get is a back screen with white writing saying there is no operating system??