Avast Locks Up my Internet

[Fire Monkey]

I just downloaded Avast - it seems to work well scanning my HDs but after I installed it I could no longer access the internet and several programs on my system would not launch.  I removed Avast and everything worked fine again.  Now the obvious thing is to not install Avast, but that leaves me without virus protection so that's no good.  I'm hoping someone will know what the problem is and how to fix it.  Here's my system info:

I run Win98SE on a 700Mhz Pentium with 765 Meg of RAM, I have a 1.5 Gbit ADSL internet connection and I am running ZoneAlarm 2.1.25 and MemTurbo 2.0 and I use Pegasus Email Client.  I did not have Avast Email protection turned on.

I hope that gives enough information and that someone has a clue what the problem is because I'd like to be able to use Avast.

[Lisandro]

Seems that something is blocking avast...
Into the firewall settings, the following programs should be allowed to connect:

C:\Program Files\Alwil Software\Avast4\ashWebSv.exe (avast! Web Scanner)
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe (avast! e-Mail Scanner Service)
C:\Program Files\Alwil Software\Avast4\Setup\avast.setup (avast! Update executable). This is a temporary file that just appears when an update (check) is about to launch, and disappears again afterwards.

Don't need rights to connect:
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe (avast! Update Service)
C:\Program Files\Alwil Software\Avast4\ashServ.exe (avast! antivirus service). Although, ashServ.exe sends ping packets to find out if the Internet connection is alive. You can turn this off by checking the "My computer is permanently connected to the Internet" box in the avast Program Settings > Update (Connections) page.
You have to manually configure browser to access Internet using avast! WebShield if you have Windows 98\Me. For 2k\XP\Vista it's automatic and transparent.

To manually configure your browser see the following tutorials:

For IE and permanent connection users:
http://www.avast.com/files/tutorials/ws_ieproxy.htm

For IE and dial-up users:
http://www.avast.com/files/tutorials/ws_ieproxy_dialup.htm

For Firefox users:
http://www.avast.com/files/tutorials/ws_ffproxy.htm