I bought a genuine copy of Windows 7 Home Premium on 31st March 2011 which was sealed. I built it onto my computer on the same day and registered the product key without any problems. Since 09/05/11 I have been receiving a message on the desktop of the
above. When trying to reactivate it informs me that the key has been blocked. I have checked my PID number on the computer and confirms I have a MSDN. How can I resolve this problem.