It wont accept my activation key

The copy that i used on the asus is the same copy that I used on the Farrari. The copy has been on the computer since November ( i had to reimage it a few times). Now I think that you can only use one copy per machine. Is that so? Now I dont want to have to clean install it again. it takes a lot of time to reinstall my programs.

I have 2 copies of professional. Now I used the unused license key on the asus and it actiated successfully. THat copy was supposed to be for my desktop but it dosent have internet access. so i used it on the asus.

2 PC's

1) Acer,are using the Recovery Disk for that PC?

2) Asus, are using the Recovery Disk for that PC?

It doesn't matter what DVD you use as they are both the same version. Since you say you have two Pro keys, then install one key on one machine and one on the other.

If you want to change the key that is currently installed, go to Change Product Key at Computer>Properties activation link. Or run this command from an elevated command line: slmgr -upk then reactivate at that link given.

If a Product Key is installed which has been used before, it may require a robocall to MS to change the hardware signature for that key in MS activation computers. You may have to talk with an agent in person. At worst, you may need to open a case with Customer Service to validate the key, after which they will have Tech Support make it work.

Be sure to remove the Product Key from any previous installations before trying it in it's new home.

I dont want to have to reimage my acer because it has lots of info (it would take days to reinstall). I installed the copy on both computers but i entered the unused license key on the asus. Then it activated sucessfully.

Thanks for the info