Here's a warning for those using the free version of antivirus software AVG, don't update to the latest database file. Or if you have already done so, don't restart it yet. If however you are unable to boot after the mandatory restart, read on to find out what to do.
PC World - If you haven’t already downloaded the latest mandatory AVG 2011 Free software update, it may be best not to if you want your computer to turn on again. The December 1 update is causing 64-bit PCs running Windows 7 to totally breakdown.
Click here to find the instructions on how to solve the issue.