Since the launch of the new version in July, it is impossible to run the looking for viruses from the start function. I have informed Avast and they have asked me all kind of information, but I can´t provide it because the messages on the screen last just a few seconds and it is impossible to print them or take a picture. I am totally sure the cause is a mistake by Avast on the July release, as I had a similar problem a year ago with another new version, and in that case I thought the problem was with my PC. After spending some money having it checked, the solution came with the new release where the mistakes had been solved. They have just released a new August version, but the problem remains the same. Releasing new versions without a proper checking seems an awful client service, expecting the client to find all the mistakes and pay the consequences of that poor service.