bad idea =.= really bad idea
Windows update actually helps with security risks.
Where did you get the solution to do a clean install and never update windows 7? I mean, there is no proof that it is because of windows update right?
Well anyways, it seems that a clean install is probably necessary. In the meantime, why not run an elevated cmd and type in slmgr -rearm and possibly get another 30 days of use?