AVG Antivirus Update Might Cause Your Windows 7 Boot Failure

If you are using 64bit Windows 7, you must be careful now to use AVG antivirus to protect your system. On Wedensday night, AVG released an update for it’s antivirus program which completely crippled Windows 7 64 bit systems and rendered them useless.

The problem leaves the machine in a continuous reboot loop. At the time of writing this, thankfully AVG have pulled the update and say it’s now safe once again to update your systems. They’ve apologized for making a mess of things and are now providing instructions on how to get your system back up and running once again.

The culprit was a simple virus definition update version 271.1.1/3292 (432/3292). The error message that appeared was

STOP: c0000135 The program can’t start because %hs is missing from your computer. Try reinstalling the program to fix this problem.

Luckily AVG have now got a couple of different fixes out, one simple quick and easy option is to boot into safe mode, and then do a system restore to before the AVG update. But in some cases users haven’t been able to boot into safe mode and AVG have a couple of different options for that too, there’s a bit of work in it though.

If you’re one of those people who have applied to update, but are yet to reboot your system and be affected by this issue, there is still a chance to save your machine. You need to find the preparations folder located at C:\Program files (x86)\AVG\AVG10 (64-bit systems) and delete it. You should then be able to reboot as normal.

If you still haven’t managed to get yourself sorted, AVG say they will be releasing a tool to sort it all out over the next couple of days, but if you’re still really stuck, try the AVG forums.
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