Last encountered error: Cannot connect to download 6.avast.com (unknown 80).
But avast is running and internet connection is live for all other activities. System is XP Home Edition, with all updates.
Do you use firewall? Are you sure it is not blocking avast?
Yes, use Zone Alarm, but have turned it off to do the updates. THis is the second time it happened to me. I believe the first time they directed me to a different update location, but can’t remember what it was.
If you close ZA and you can update avast, it has nothing to do with avast’s different download servers (to spread server load), rather ZA is blocking avast.setup, this must be allowed internet access to be able to update.
Besides what David said, can you tell us when did that occur and how do you connect the Internet?
I mean, a manual or automatic update, at boot time or whenever you try… etc.
I am familiar with Zone Alarm blocking sites, and I did check for that, it is not blocking avast. I connect to the internet with DSL and it is an automatic update. So whenever the automatic update tries to occur, which is every day now.
Maybe I’m confused but how do shut down ZA for an automatic update of avast!
when you have no way of knowing when that update is going to happen?
I shut it down and tried to do a manual update and got the same error message as when the autoupdate tries to run.
Have you tried to clear all program permisions in ZA (I don’t know is it possible to do, kerio can remove them) and to configure ALL PROGRAMS permisions once again? Besides, if I was you, I’d reinstalled both avast and ZA. but it’s just my opinion… 
The only time you can reset ZA permissions as far as I know is when you don’t want it to happen. If I ever need to do that I uninstall and then reinstall ZA. Couldn’t find anything in the help section sorry
We are not talking of blocking sites here but blocking avast.setup accessing any internet connection. That is why when ZA is disabled, avast.setup can connect, check and see if avast.setup is an allowed or blocked program/process.
Leave ZA on and do a manual update, you should be asked permission for avast.setup if it isn’t an accepted program/process.