I just bought the full blow version of Avast am now unable to connect to the Internet. This is not a problem with downloading web pages; the computer cannot connect to DNS to resolve addresses. I tried turning off all Avast services for a few minutes with no improvement. I finally uninstalled Avast and the computer connects to the 'net just fine. Reinstalled Avast and the problem returns; no connection. Anybody figured this out?
Thanks very much.
Joe.
What full blown version of avast (avast internet security, AIS) ?
The reason I ask is I believe the firewall element of AIS wasn’t compatible with win2k.
What version number 5.0.507 is the latest version number ?
I don’t know if this update has changed that or not.
OK I have had a rummage round the avast site, http://www.avast.com/internet-security#tab1 and it doesn’t list win2k on the compatibility list for AIS, see image.
… but free version (without firewall) is running well with windows 2k! 
Yes, but that’s the point, the Original Poster is using AIS and the requirements in my image are for AIS and win2k isn’t supported.
Hello David,
nice to read you!
Yes, I understand the differences now. Thanks for explanation!