Yes it was while updating to version 4.7.1001 that the problem turned up. I had uninstalled it when not able to connect to the net anymore. Now I have (useing the xp installation on a different partition-) downloaded the setupger.exe <I am a British guy living in Germany - have a German OS> and done an install from scratch in the vista x64. There is still no access to the net there.

(Perhaps it is relevant that I use the c-fos packet shaper. But all was well with this also running alongside avast untill this recent attempt to update avast.)

Thanks for your assistance…