Strange Internet connection

[toonei]

A friend of my is having internet connection problems.

The computer is a new Dell running Win XP Home, no software firewall or XP firewall enabled, and no ICS, just a stand alone PC. We live in Alaska and get our service through GCI, it is very reliable and consistent. Have talked with their Tech Support and his connection shows up good on their end when he is connected.

His internet connection is through a cable modem. When you boot the computer sometimes you can get an internet connection, sometimes not.

Doing an ipconfig /all shows a public ip address, gateway, dhcp server, dns address etc. If you do an ipconfig /release and then ipconfig /renew you are able to get a connection,or by powering the modem off and then on again. I have also tried flushing the DNS cache. Once you have the internet connection it holds it, once you reboot or shut down the computer it is the same thing all over again.

1. I have swapped out the RJ 45 cable going to the modem with a known good one.
2. ISP has replaced the modem and checked their wiring.
3. I have tried another NIC card, drivers are installed and link lights working, no problems in System properties showing with either NIC. I disable the onboard NIC before installing the new one.

I brought this computer to my place and set it up, I use the same internet service provider, it works fine.
I have set it up in the same building where he lives connected to another modem of the same type, with the same ISP and the computer works fine.

Here is the glitch that I cannot figure out. In both of the above setup scenarios this computer was hooked up to a router and then through the cable modem. Works fine. Connection is consistent, never a problem.

If you plug the computer directly into the Modem, the problem returns, I have also used another good working modem so a bad modem is not the problem.

So why does this computer only work consistently when it is behind the router? and not hooked directly into the modem.

Hope someone has an answer, this has been a real hair puller.

 

[thedaver]

Sorry, but what's the problem here?? Good background, but I don't see the problem clearly.

Surfinbox.com Business Internet Services - National Dialup, DSL, T-1 and more.

http://www.surfinbox.com/business/

 

[toonei]

The problem is that the computer will not get an internet connection unless it is behind a router. When hooked directly into the cable modem you have to inpconfig /release and renew to get a connection. Once you have a connection it will hold. If you reboot the machine you have to do the same thing all over again. Any ideas?

 

[thedaver]

Do me a favor, go through the connection process to the Cable modem directly one more time and copy down the output of 'ipconfig' before and after you do the "release/renew" cycle.

I have a guess but I don't want to float it without seeing the output.

Surfinbox.com Business Internet Services - National Dialup, DSL, T-1 and more.

http://www.surfinbox.com/business/

 

[toonei]

Thanks to "thedaver"...Your post got me to thinking about what I had been looking at when I did an ipconfig on that machine. I went over to my friends place and did it again. There was another connection showing. When I looked in Network Places there was an Icon for a Direct Line? Had usual protocols, file and print sharing, TCT/IP. Also a tab showing his modem and a couple of other things, none were checked.

Make a long story short, I deleted the connectoid--all is working fine. I have never seen a connection like this in XP before, usually XP will try and put a bridge connection in Network properties when none is needed, but this was different.

Guess I was too caught up in one frame of thought and missed the obvious. Thanks for the memory jolt....