AVG update shatters Windows

Users of the popular AVG anti-virus program were left with unusable systems today as the result of a botched signature update that rendered PCs unbootable.

The issue, which AVG discusses in its support forum, stems from a bad update to the software's virus signature files that causes systems running a 64-bit version of Windows to reboot and hang.

The affected systems display the following error message: "STOP: c0000135 The program can't start because %hs is missing from your computer. Try reinstalling the program to fix this problem."

Sadly, the fix isn't exactly straightforward for the non-technical: because the flaw causes Windows to load the bad file each time the system is restarted, a user needs to enter the command line and manually rename the folder in which AVG is installed to prevent it from loading at start-up. Once this is done, the system can be rebooted and AVG re-installed without the damaged file.

AVG issued a statement to customers asking them to "accept our apologies for any inconveniences caused by this situation," but - embarrassingly - most of the solutions for the problem have come not from the company's team of support engineers but rather from end-users posting on the support forums.

For those who are unable to recover their systems, AVG asks that they 'stay tuned' to the official support thread for more information - although they'll clearly have to use a second PC to do so.