so hard to guess where this keys are coming from. would you mind to give 10 keys to a trusted member here so he can verify them with MS? If they are clean, it shouldnt be a problem.
I wouldn't mind at all to be honest... if it's a member from the US, Microsoft even has a phone number to check the keys
But make him CHECK the keys, not use them because i don't want to loose 10 keys like this.