No problem IOBit messes the tcpip and winsock
Another bad service of IObit to the humanity? 
Hmm. Nothing seems to be working for me except disabling the Web Shield.
Here’s what I’ve done so far.
Uninstalled IOBit Advanced Windows Care. Rebooted. No fix.
Ran Repair function on AVAST Free. Rebooted. No fix.
Ran Winsock/TCPIP repair tool found in this thread: http://forum.avast.com/index.php?topic=65843.msg556012#msg556012 and then rebooted. No fix.
Ran Winsock/TCPIP repair tool found in this thread: http://forum.avast.com/index.php?topic=65054.0 and then rebooted. No fix.
I am running only Avast Free and Comodo.
Any ideas?
Did you try this ms fixit plus the ones I posted two posts up ?
http://support.microsoft.com/kb/811259
Hi, I have performed both your fixit suggestions and the am now able to surf the internet,however, my windows firewall keeps being turned off and when I turn it back on again I am unable to surf the internet.
Do you have any suggestions please
Regards
John.
Do you have a third party firewall ?
Did you have another antivirus previous to Avast ?
If so what was it ?
I used microsoft Essentials before installing Avast but that was removed after I installed Avast.
John.
You should remove microsoft Essentials before installing avast!
I would do a clean install of avast!
How to install avast! Free Antivirus 5.x?
https://support.avast.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=564&nav=0,1
Hi, I have done as you suggest and still have the same problem with the windows firewall. Should I install an alternative firewall ??
I also disable windows defender in case this was causing a problem.
Regards
John.
Hi essexboy. Thanks for your help. I tried that ms fixit plus the ones you posted two posts up, and no change.
I also tried the manual netsh winsock reset c:\resetlog.txt command after running command prompt as admin. Oddly, though the command seemed to process, no c:\resetlog.txt was generated that I could find in c:\ after rebooting. I’m running Windows XP Pro (in case that is relevant).
Any ideas?
I too wondered about that run command. I’m used to seeing a > used to indicate an output file.
Try this command and see if it generates the file:
netsh winsock reset > c:\resetlog.txt.
Yep that worked; it generated the file. I’m going to restart before I post the contents.
edit: okay, here’s the contents:
Sucessfully reset the Winsock Catalog.
You must restart the machine in order to complete the reset.
There it is; complete with the misspelled “successfully.” No change… Still blocking http.
I still don’t understand why, if it were a problem with Winsock/TCPIP, then why would https work? e.g. http://www.google.com fails but https://www.google.com works. It’s not my firewall; everything worked fine before, and https is still unblocked by the firewall. After so many Winsock fixes, it seems like it has to be something different…
Https content isn’t monitored by the web shield, where http port 80 content is.
Let me hop on this thread as well 
I just installed a fresh copy of Windows XP SP3 with ALL current Windows Update content.
Got the Avast! Free from Download.com and installed. PC has currently NO other programs or content installed.
Still, I do have the same problem as discussed in this thread. The moment I turn Web Shield OFF, all traffic is restored, turn it back ON, nothing whatsoever.
Also, running a second machine here, same engine/updates but on Windows 7 64bit, that one had no problem (posting from it atm…)
Tried a lot, if not all tips I have found here, all the way up to disabling the MS Firewall, but until now, the only working solution is running without Web Shield…
[EDIT]
I now have the system up and running WITH Web Shield turned on, however, I had to uncheck the “Scan Web (HTTP) Traffic” part.
[/EDIT]
That is the same as effectively disabling the web shield as it only scans http traffic.
To original poster. I note you are using Vista.
Vista does from time to time have problems with TCP Auto Tuning.
I had the exact same problems as you. Solved(very simple to do) by following instructions at http://www.mydigitallife.info/2007/03/22/disable-tcp-auto-tuning-to-solve-slow-network-cannot-load-web-page-or-download-email-problems-in-vista/
Yes, I know. My point was simply that the fact that http apart from the Web Shield and https in general are both functioning is evidence the problem is located in the Web Shield rather than with Winsock/TCPIP as for some others, especially since the Winsock/TCPIP fixes did not resolve the problem on my computer. Hopefully, this issue will be fixed in the future. Until then, the only recourse appears to be to turn off the Web Shield while leaving the other fully functioning shields on.