I have been using this genuine software for years. I had to rebuild my PC at the end of 2012 and it was OS activated after changing a c drive. On 19 Jan 2013 it I got a message saying Activation time had expired and I got a permanent message "This copy of Windows is not genuine". It is in build 7061. However the internet functions are still running OK. Trying to activate it now the correct keys are not accepted.