DavidR
2
Don’t disable the windows win7 firewall, by default it doesn’t have outbound protection enabled, so shouldn’t be getting in the way.
You say you haven’t got another AV installed, but did you ever have another AV installed ?
If so what was it and how was it removed ?
What errors are you getting when you try to connect ?
Again disabling avast completely leaves you very vulnerable, since you also have the firewall disabled. Try just disabling the Web Shield as that is the only direct interaction with your internet browsing.
Are you able to connect to HTTPS secure URLs ?
e.g. can you connect to this secure connection to the forums https://forum.avast.com with avast end the web shield enabled ?