Hello Thread Starter and Alwil-Software!I just registered in order to tell you something about this issue, which is well known and seems to be random to different users on different machines year after year and by many different Internet Security Software.
My reply goes to nat1 but Alwil should have an eye on it as well:ref 1.:
http://forum.avast.com/index.php?PHPSESSID=c29f45179af56588aac91cda550bc01e&topic=57922.0ref 2.:
http://forum.avast.com/index.php?PHPSESSID=c29f45179af56588aac91cda550bc01e&topic=58420.0ref 3.:
http://forum.avast.com/index.php?PHPSESSID=c29f45179af56588aac91cda550bc01e&topic=58420.msg492458#msg492458(This are just some reference links the thread starter and other people already tryed out to solve the problem.
And ref. 3 is a solution that may work and I tried but didn't worked out for me years ago, so don't scream to loud too mate, I guess you have'nt had that problem at all)
The description nat1 and other guys have made so far reminds me of problems I experienced in the years around 2000~2002 when I bought Norton Internet Security Software.
I read some threads in this forum related to the problem ISSoftware blocks any connection to the Internet or even in some cases to the router itself. And every advice which was here given I tried myself years ago too!
I must mention I regularly don't use dual, tripple or how many OS's are bootable on my computers. I only use one OS and I'm just fine with it.
As I said I could recall every problem, solution tries and where they led. I was able to follow those which were described here.
I could be wrong but there was no solution found even by Symantec. Nowadays everytime I talk to people who had the same issues there's no one who wants to use any ISS anymore. All of them are using different programs for their own individual internet activities. And here in my country IT people have a dictum: Don't buy an all-purpose-IS-program because sometimes it leads to a total block of your machine and there's nothing you can do.
I had error-messages, failures, blocks, won't-start-problems even in safe-mode and certainly BSOD's! Although I tried several reinstalls of my OS, of ISS, I enabled ISS settings or disabled, with or without firewall, clean installs and whatever you can imagine there must be a solution!
I tried years ago because I had time to do all those time consuming things, but I put about 12 days each ~ 12 hrs of work in it. But I didn't manage to solve this issue. Not only I did.
And the oddest of all was I disabled the whole ISS, by deselecting autostart options and all other program functions, restart and everything seemed to run pretty good. 4 restarts later -restart by restart machine went slower- and my OS was dead. It didn't start up welcome screen nor blank screen between Bios post...only BSOD everytime with different and absurd messages of what has caused the failure and all in all there was no thread.
Therefore I'll give you advice configure your machine respectively your OS whatever it is with different programs to get your own personal security depending on your prefered usage. There is no universal program that gives you perfect security.
If Avast IS or any other ISS works for you - bingo! For me not, thank you.
I honestly respect what AV-Companies try to give all of us - thank you all for your hard work and efforts to protect us.
I tried several AV-Softmachines and Avast! is my prefered atm. And they're going to add (hopefully

) a sound-volume-regulator and for some german speaking people the nice swiss-speaking guy who reminded us with his perfect dialect so often that Avast is updated

, that'll be great (post this on the wishlist later).
So what I want to tell Alwil Software, if there's one out there. Please be careful of what your think tank is trying to do.
There are several peoples out here, who had bad experiences with the multipurpose idea and they don't come back to that product where the issues began.
I like and I recommend everyone to try the trial versions and if satisfied buy Avast! Antivirus Pro especially to native german speakers. Avast is a very good AV program and it was inconspicuous in need of computer resouces (just installed version 5 - can't tell if it's still status quo but I believe so)!
Best regards!