Black Screen

Hi. Subscribed to AVG Ultimate last week. Yesterday I cleaned up using AVG. Today I turned on pc, received message that pc was updating and not to turn it off. Two hours later it was still updating, then the screen went black with just a couple of icons flashing on the bottom toolbar. I spoke to tech support in Germany. They sent instructions by email which were downloading AVG Reset Access, AVG Clear, AVG Remover and then reinstalling AVG Ultimate. Eventually I got some apps showing on my desktop so I managed to ope Firefox and read the email. I tried to download Reset Access but just got the message Server not Found. I dare not try anything else. I have read comments on support page that Reset access ruined their pc. Should I ignore that download and instead try Clear and Remover.      The pc is behaving strangely, font is different, facebook is different, my keyboard is all mixed up with keys not operating correctly.   I wrote to Romeo in germany but he has not replied. This is the fault of AVG and I would really like some decent service. Thanks