installation problems

[jnz]

I installed Avast! on two XP computers and lost internet connection on both computers until I unistalled Avast!. I assume that the issue is a conflict with Avast! and Lavasoft firewall 3.0. What permissions or special setup is required in Lavasoft to make this work?

[DavidR]

It is blocking the Web Shield, inadvertently blocking internet access.

Does it allow avastSvc.exe internet access ?
- If it does delete the entry for it and reconnect to the internet, this should force the firewall to ask permission again.

[jnz]

I set avastSvc.exe as a trusted application, but still had issues with internet access. I may give up and stay with the current anti-virus.

[DavidR]

<snip>I may give up and stay with the current anti-virus.

Well by current, do you mean that you still have it installed on your system ?
If so that could be the root of the problem.

Having two resident scanners installed is one too many and not recommended as rather than provide twice the protection it can cause conflicts that could leave you more vulnerable. These conflicts could present themselves in many ways and connection to the internet is just one.