try installing spywearblaster , i had problems with the computer crashing at home and it stated refusing to update the avg, i installed it and it now updates the virus checkers and spywear removers with no faults, i had a downoader.agent virus that avg couldnt find or remove till i installed spywearblaster to block the thing reinstalling , once that was running ii could update the virus software, then avg found the virus, it still wouldnt remove it, but found it, you need to manualy delete the file if it finds it, then update the virus checkers, preferably by clean install of the virus and spywear software then update it, not just updating them without reinstalling
