My MVPS HOSTS file has these relevant entries...
# 127.0.0.1 ssl.google-analytics.com #[disabled = Firefox issues]
127.0.0.1 www.google-analytics.com #[Google Analytics]
So I unblocked www.google-analytics.com in my HOSTS file, and it appears that is the culprit! The avast website works correctly for me now (pending further tests) using either Firefox 3.6.18 or Internet Explorer 6.
Note: ssl.google-analytics.com block was disabled by MVPS HOSTS file developers, because they found a related problem with Firefox. I'm not privey to those details.
At this point, I have no further details about www.google-analytics.com nor its purpose but will try to find out something. Does anybody know what it does, or why the avast website is using it?
I have google-analytics.com and www.google-analytics.com entered into HostsMan's Exclusion Lists...
I do not have ssl.google-analytics.com disabled though.
You should upgrade to Internet Explorer 8 as IE6 is quite old.
Please pardon my shaggy dog tale below...

I still haven't tried Hostman's utility. I use a text editor which works fine. What matters is that an entry exists in HOSTS file, or it doesn't. If your computer works differently than mine at the avast website, both having the following line in HOSTS file, then it's another mystery to be solved:
127.0.0.1 www.google-analytics.comI don't have a google-analytics.com line (the non-www format) in my HOSTS file. It does not appear in the most recent MVPS HOSTS file version (July 23).
I've tried IE8 but it's incompatible with Outlook Express on this XP Home SP3 computer, and I'm not going to change my email client. I don't care how old IE is, because I don't use it on this computer. I use Firefox 3.6.18 as my default browser. I strongly doubt that's the cause of my problems at the avast website. So to prove (or disprove) my point in that regard, I've gone another mile down the road, as follows...
I have another computer available here that runs XP Pro SP3 and IE8, which doesn't have the MVPS HOSTS file, only the rudimentary example HOSTS file that comes as default. It has no problems with the avast website. As an experiment I added a single "127.0.0.1
www.google-analytics.com" line to its HOSTS file and here is what happened...
If I goto
http://www.avast.com/en-us/index and click the FOR HOME tab at top, IE8 puts a yellow warning triangle on status bar to show that there are problems. If I click the yellow warning triangle, it says: Errors on this page might cause it to work incorrectly. Webpage error details. User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1)...
Message: '_gat' is undefined
free anti-virus download
Line: 54 Char: 3 Code: 0
URI:
http://www.avast.com/en-us/free-antivirus-downloadMessage: 'pageTracker' is null or not an object
free anti-virus download
Line: 62 Char: 3 Code: 0
URI:
http://www.avast.com/en-us/free-antivirus-downloadMessage: 'pageTracker' is null or not an object
tabs.js
Line: 31 Char: 4 Code: 0
URI:
http://static.avast.com/j/tabs.js?t=201107221222Message: 'pageTracker' is null or not an object
lightbox_free-antivirus-download.js
Line: 48 Char: 9 Code: 0
URI:
http://static.avast.com/j/lightbox_free-antivirus-download.js?t=201107221222Message: 'pageTracker' is null or not an object
free anti-virus download
Line: 31 Char: 1 Code: 0
URI:
http://www.avast.com/en-us/free-antivirus-downloadThe tabs near the middle of that page are inactive (go nowhere): Why AVAST, System Requirements, Technology, More Options. I've already posted the relevant graphic in this thread somewhere above.
If I click on the Free Antivirus DOWNLOAD for home use only* button, it pops up a page where the "No thanks, I want free protection" button is inactive (goes nowhere), and it is still showing the same page errors as listed in detail above. I also posted this relevant graphic somewhere in this thread above, IIRC.
Firefox 3.6.10, Chrome 12.0.742.122, and Safari 5.0.2 give exactly the same results as IE8 on this XP Pro SP3 computer, once again confirming that these bugs are *NOT* browser related!
I believe this shows conclusively that the avast website bugs (subject of this thread) are caused by incorporation of
www.google-analytics.com into the avast website coding. I should say that I somehow suspected that google might be involved before I began this investigation due to the fairly recently bundling of the Chrome browser offer with the free avast antivirus installer. In effect the free avast antivirus is only available for download now if user consents to being tracked and traced by google. Of course I don't know if this is by design or accidental, but suspect the former.
P.S. As the final nail in the coffin of other theories, I then removed the 127.0.0.1 www.google-analytics.com line from HOSTS file on the XP Pro SP3 computer. Result: no errors or problems at the avast website. This leaves absolutely no doubt about the cause.