Odd networking problem

[Ric_]

This job was a problem for a friend... one that has baffled me!

 

Laptop (XP Pro) connects to a network (wireless) fine but IE cannot load a page. Pinging websites (e.g. Google) works fine. DNS queries aren't a problem.

 

I installed Firefox and that also would not load web pages! This got me thinking... telnet to port 80 at http://www.google.co.uk gave "connection refused" (IIRC) as it did with other websites.

 

Booting to Safe Mode allows connection to the web fine so it must e some dodgy app running in the background. I disabled all non-essential services and installed Spybot S&D, Adaware, AVG Antivirus and AVG Antispyware. These threw up very little (you're normal toolbar things and that's it).

 

Netstat showed nothing was using port 80 so what's going on?

[m25man]

If it's IE7 just use the reset button in the advanced tab of Internet Explorer Options.

 

This undoes all IE mis-configurations and resets it back to factory.

[Domino]

checked the router config to check the HTTP traffic is going through?

[Guest Guest]

You checked the advanced TCP/IP options in network connection? Maybe possible something has managed to blacklist port 80

[PEO]

cleared your internet cache?

proxy?

have you tried .com, .net etc?

can you logon to msn messenger?

disabled firewall(s)

[Guest richard]

Tried using a live cd like PCLinuxOS 2007 or Ubuntu and seeing if they can view webpages?

[DMcCoy]

I suspect that it had some malware on it that has been removed. I've seen this before where it takes over resolving dns which then breaks when its been removed. Only way I fixed it was with a fresh install.

[PEO]

rather than a fresh reinstall you can refresh the tcp/ip stack http://support.microsoft.com/kb/299357

[DSapseid]

I've seen this before where it takes over resolving dns which then breaks when its been removed. Only way I fixed it was with a fresh install.

 

I have also seen this a few times before and the only way to fix it is to reinstall the OS.

[JamesC]

Try disabling 'Automatically detect settings' (if it is enabled) located in:

 

internet explorer -> tools -> internet options -> connections -> lan settings

[djm968]

Is IPv6 is installed?.... If it is uninstall it.

[Joanne]

i got this problem too! Acer told me it was software, so I rang the software people and they said it was ISP!! but I've changed from Vista to XP and having the same problem so I'm sending the damn thing back to them!

 

Tried it in 3 places with different routers and ISP's but did the same in each place.

[strawberry]

If it's IE7 just use the reset button in the advanced tab of Internet Explorer Options.

 

This undoes all IE mis-configurations and resets it back to factory.

 

its not as complete as you'd think, might be worth an ie reinstall.

[dhicks]

Did your friend's broadband ISP send them a CD with some kind of installation utility on? These are completly uncessary, Windows can connect to a broadband connection just fine by itself. Some installation utilities conk out halfway through, leaving half-installed software that's trying to do something or other with your network connection, that might be your problem.

 

--

David Hicks

[Ric_]

OK... we are using a vanilla wireless connection connected to a known good ADSL router (Netgear IIRC). AFAIK no software has been installed but if it has it has been removed.

 

I did not have any gubbins with me to test (I was having a quiet drink in the pub at the time!). As mentioned above, Safe Mode with Networking works fine.

 

No IPv6 and I tried IE6 and Firefox. As mentioned, telnet will not go out on port 80 to fetch pages either so it is not a browser mis-configuration.

 

DNS still works fine... pinging a DNS hostname resolves the IP fine and running nslookup also works fine - tried different DNS servers too just in case.

 

I think I checked that port 80 was getting blacklisted in the advanced properies. I obviously disabled any firewalls.

 

I suspect it probably is a mangled IP stack and the reset thingy may do the trick.

[JamesC]

how about trying:

 

sfc /scannow

 

(the built in system file checker) from command line to replace all key operating system files?

 

This command will actually initiate Windows File Protection to scan all of the protected operating system files, verify their integrity and replace any files with which it finds a problem.

 

EDIT:/ you also say that Telnet will not work on port 80, have you tried accessing a web page using HTTPS? Does this work?

[Ric_]

Finally fixed this problem but I had to use the recovery partition and blitz the machine

 

I tried all the recommendations above for resetting the IP stack and running sfc, etc. to no avail. This truly was a strange problem.