Windows 7: Windows 7 home edition

I am a total newby --how does my computer know if these disks i have - have been installed before?

Could you be more specific? "These disks" could be anything. If they are disk that came with the computer, chances are everything on them have already been installed.

Please name the disks that you are messaging about. Also please give complete specs of your computer for meaningful help.

As Petey7 has indicated they are probably already installed.

If I understand what you're asking: your computer doesn't know.

However, the latest three versions of Windows (XP, Vista, and 7) all require activation. Microsoft maintains a record of whether a license key has been used.

That's for retail and OEM licenses. I'm unfamilair with corporate licenses, but I believ that they're handled differently.

I have an older DELL -(PC) that quit working so I bought a new 27" Imac - capable of having the best of both worlds -- with a quad chip - and 3.1 Mhz speed.

I doubt if anything has been installed on it.

I spoke to MICROSOFT on a land-line last nite-- man are they rude! --

I explained my situation --and I was NOT at any of my PC computers. I did find out though that even though I am allowed to be running 3 different computers with my Windows 7, 1) I CANNOT sell any one version to another person, but I CAN GIVE A COPY of it away!