Crazy network problem

Hi there,

We're having a crazy network problem here at work...

Basically we have 2 computers (1 toshiba laptop and a IBM desktop) who cann't connect to internet with IE but FF is very slow. On IE it seems to find the page later it indicates it's waiting for reply and finally after waiting for about 10minutes we get a Page Not Found Error. FF is just slow you can load pages but at times certain images wont load or other pages only load half way. For example if you perform an google search with FF only the right hand Adverts are returned but not the actual search results itself.

All other machines on the network can connect perfectly but these 2 can't seem to connect no matter how we try... we've tried changing DNS settings, assigning a static IP also thought it might be a virus so we've scanned them with Norton, Search and Destroy but still cann't connect.

The oddest part is if you take the laptop else where and connect to another external network (at home or something) IE and FF work perfectly. Seems to be a connectivity issue with it in our internal network.

Any body has any ideas?? Any help is highly appreciated.

Thanks.

 

Sure sounds like a DNS issue to me. The fact that its only bringing up a few adverts and nothing else tells me those are coming from cache, not an active connetion.

If you've got a DHCP server on your network that is passing the DNS addresses, make sure to remove the DNS servers listed under the adapter's settings. Then do an ipconfig /release & ipconfig /renew and try it again. If its still not working, try an ipconfig /flushdns and try once more.

One way to determine if its a DNS issue is to go to your command prompt (not run, the actual command prompt) and type "nslookup". Then type the name of a website you were trying, such as www.google.com. It should immediately respond back with that ip address. The first section returned is the dns name and ip address of the dns server that is being queryed. The second section is the dns name & ip address of the server you were querying; in this case, google.

You can then try to ping that address. Many company firewalls dont allow incoming/outgoing ICMP and some websites dont respond to ICMP so this may fail for other reasons, but if you've tested from a working pc and the ping works, then this might be a good try.

One other suggestion I have is to open command prompt, type "telnet" and then "open www.google.com 80" and then "GET \index.htm". You should start seeing a bunch of HTML code. If you dont, then you can confirm its not a browser issue (but it shouldn't be since you're able to use the browser at home)

Finally, make sure there are no funky proxy settings set up in Internet Options. I'm not a big fan of the "automatically detect settings" option either, though this shouldn't be causing your problem.

 

In General, you can debug the Network Setting of the computer following these steps.

Step One. Check the Network parameters in the Computer's Device Manager. Make sure that the drivers are installed correctly; there is No IRQ conflict, and No Ghost installation. http://www.ezlan.net/faq#ghost

Step Two. Verify Basic network setting in the OS: http://www.ezlan.net/Installing#verify
If the above two Steps indicates that every thing looks good but functionally it does not work.

Step Three. Check (and repair if necessary) the Socket Layers, Winsock, and or refresh the TCP/IP Stack. http://www.ezlan.net/clean#refreshnet

 

Cat5e... he says the the laptop works fine at home, so I don't think that this is a drivers issue. Its obviously a DNS problem, because he only experiences the problem in the office, which would be using a different DNS than what he uses at home.

 

In the process of verifying (part of the above post) the OP should look at the DNS if it is not on Auto but set to specific IP it would work only with a system that has this IP.

 

My thoughts lean toward a network issue/problem where those two pc's are connected. Are they both wired to the network or wireless? Are they connected to the same hub/switch? Can you take a known working pc and connect it where the failing ones are connected and have it work? If a known working pc works in the failing pc's location, then your problem is isolated to the pc but I assume a working pc will fail when hooked up to the failing location.

-Jim