Problems resolving internet addresses - returning DNS Error

[spazdragon]

I'm running XP Pro on a desktop PC and a laptop. Both are connected to a wireless router (The laptop is connected wirelessly and the PC via an ethernet card & cable). The router is connected to BT ADSL. I set the network up a couple of days ago. Before that, the PC was connected to the same ISP directly through an ADSL modem with no problems. My new setup has all worked fine for the past couple of days but this morning, both machines started to have problems resolving internet addresses. I can ping IP addresses and use the IP in the IE address bar; I can get to Google using

http://66.249.87.104/

but not

http://www.google.co.uk/

IE is now not resolving most URLs, but some do work (such as this one).
Has anyone got any idea what's going on? I'd very much appreciate any suggestions.

 

[bcastner]

faq779-4625

 

[spazdragon]

I've tried the netsh.exe solution and then the winsockfix app, re-booting after each, but still nothing. I'm running Alwil's Avast! anti-virus, Spybot-Search&Destroy and windows firewall.

 

[bcastner]

Are your settings for your network connection "Obtain an IP address automaticly"? They should be.

Check too under the network properties sheet, Internet Procolal (TCP/IP), Advanced, that there is nothing set for DNS or under the WINS tab.

 

[spazdragon]

Obtain an IP address automatically is checked and in 'Advanced' I have:
---------------
|IP Settings|
---------------
DHCP Enabled
[checked]Automatic metric
-------
|DNS|
-------
[checked]Append primary and connection specific DNS suffixes
[checked]Append parent suffixes of the primary DNS suffix
[checked]Register this connection's DNS suffix in DNS registration
--------
|WINS|
--------
[checked]Enable LMHOSTS lookup
NetBIOS setting [checked]Default..
-----------
|Options|
-----------
Optional settings: TCP/IP filtering..

 

[bcastner]

---------------
|IP Settings|
---------------
DHCP Enabled
[checked]Automatic metric
-------
|DNS| <-- these only matter in a Domain setting
-------
[checked]Append primary and connection specific DNS suffixes
[checked]Append parent suffixes of the primary DNS suffix
[checked]Register this connection's DNS suffix in DNS registration
--------
|WINS|
--------
[checked]Enable LMHOSTS lookup
NetBIOS setting [checked]Default.. <-- set to enabled
-----------
|Options| <-- do not change
-----------
Optional settings: TCP/IP filtering..

==============================

New steps:

1. Set the router to a manual MTU setting of 1492 instead of its default of 1500

2. Download and apply on both desktop and laptop the DrTCP freeware utility, and set the network adapter to an MTU of 1492. It is important to reboot after this step:

http://www.dslreports.com/drtcp

 

[spazdragon]

Ok, that's made a lot more sites accessible via the URL. I also turned off 'Use intelligent stream scanning' in Avast! and that helped a little bit too but there are still some sites returning a Cannot find server or DNS Error.
Thank you for your help so far though, at least my pop3 & smtp servers are being found so I can use email!

 

[bcastner]

Okay good. We eliminated PPoE errors.

I wish you had specified what service pack level you were using, but:

http://support.microsoft.com/default.aspx?scid=kb;en-us;813444

http://support.microsoft.com/?kbid=813951

http://inetexplorer.mvps.org/answers2.htm

 

[spazdragon]

It's SP2. The only problem with the links above is that I can't access them. I get the Page Not Found error if I use the URLSs and if I try pinging them I get 'Ping request could not find host...' :/