|Usually you can go to microsoft and look up your error code sometimes that helps|
hmmmm let me see....checking their website......
"activation key already in use"
So, if you have a legally purchased laptop, that has a valid microsoft sticker and you know everything should be legit (ie: you didn't give 10 friends the code so they could have vista free), then what you do is you go back into the activation part and select to activate by phone. They put you through some small easy hoops, you enter the code generated and it will get reactivated. If microsoft will not activate this for you by phone you have an issue and will ask to speak to an agent, you can explain it to them.