According to Windows Security Centre, Firewall, Auto update, Malware protection are all on and other security settings OK. No difference when Anti virus is off. I have not done a driver check recently - but will do so. Just a point though regarding only running one firewall. At one stage, I did install Avast - but then removed it. I wonder if it is possible that some part of that did not uninstall properly and is affecting things? I don't know enough about computers to know if that is a possibility or indeed how to remove something thathad been left behind. Thanks for your help - I'll keep trying. Regards Barry