I have no other on demand scanners installed. My firewall is the Win XP SP2 firewall and probably the WLAN router inbuilt hardware firewall is doing sth. as well. In the meantime i tried so solve the problem by a complete de-installation and re-installation (with complete startup scan). This did not help. Alwil is listed on the microsoft page of the partners for virus detection on so I believe it must be a bug within the latest avast 4.7.871 (German) version not to get detected. I don’t believe it’s a really thread and unchecked the virusprotection check in the security center options. I hope help will be on the way.

@Barr_y: Thanks for your reply. It’s good to know that I’m not alone :slight_smile: The restart of the security center did not work for me. Do I have to terminate any process within the taskmanager before I restart it?