Network DHCP Problem

[Yuxi]

Hi,

Today, suddenly my main computer can't get an internet connection. Or even get an IP address from the Linksys BEFSR41 v2 router at all. In the Network Connection status dialog, it says "Limited or no connectivity". Clicking "Repair" does not work. I restarted the computer, and everything worked fine again.

Now, the same problem happened again. Except this time restarting didn't do any good. It's a SiS 900 onboard 10/100 network card.

I've tried disabling/enabling, reinstall drivers, installing IPv6 and the IPX protocals, but it still doesn't work. I'm posting this from my laptop on which the internet works perfectly.

Any ideas?

Yuxi :crazy:

[NeoMasamune]

Sounds like the onboard NIC might be going bad. Maybe try getting a PCI NIC, installing it and see if that fixes it.

[Yuxi]

  NeoMasamune said:

Sounds like the onboard NIC might be going bad. Maybe try getting a PCI NIC, installing it and see if that fixes it.

I was afraid someone would say that. :(

Oh well, I have another PCI 100mbps card laying around here somewhere.

*starts digging in closet*

Update: The leds where the CAT5 cable plugs into the computer is constantly flashing at about 8-10 times per second. This goes on even when the computer is powered off. I'm starting to think this is a hardware problem. :cry:

Edited August 24, 2004 by Yuxi

[Caboose447]

Before you rip open your computer and start swapping out NIC's and everything, try these steps:

Before you begin, unplug the power to your router so that its off (or you can just unplug the ethernet cable)

Step 1: Delete the corrupted registry keys

Click Start, and then click Run.

In the Open box, type regedit, and then click OK.

In Registry Editor, locate the following keys, right-click each key, and then click Delete:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Winsock

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Winsock2

When you are prompted to confirm the deletion, click Yes.

Note Restart the computer after you delete the Winsock keys. Doing so causes the Windows XP operating system to create new shell entries for those two keys. If you do not restart the computer after you delete the Winsock keys, the next step does not work correctly.

After you've restarted your PC, you may get an error message from Norton Anti-Virus, or maybe McAfee. But AVG doesn't give an error message. Something about e-mail proxy. Just ignore it and close the box. Then go onto step two

Step 2: Install TCP/IP

Right-click the network connection, and then click Properties.

Click Install.

Click Protocol, and then click Add.

Click Have Disk.

Type C:\Windows\inf, and then click OK.

On the list of available protocols, click Internet Protocol (TCP/IP), and then click OK.

Restart the computer.

Shut down your PC -> May seem really odd, but do it anyway!

Plug in the ethernet cable

Boot up your PC

What may have happened is that your Winsock keys became corrupted. It happens. I work in tech support, and I see it a lot! Meh... its Windows, and it happens! :woot:

[Yuxi]

I'll try that later, but I highly doubt that some corrupted registry keys causes the NIC LED's to flash even when powered off, POST, loading windows, in windows, etc...

:wacko: :wacko:

[Caboose447]

depending on the NIC it may be on. I know that the LED's on my NIC are on even when the PC is off. 'cause a boot signal can be sent to the PC over the NIC. Its weird, but try those steps for the winsock keys! Don't knock it before you try it! It works for me every time! And I've been doing tech-support for about 6mo so far, 10hrs a day, 5 days a week! I get A LOT of internet calls!

[MazX_Napalm]

There is a know "problem" with the SiS NIC. They all come out of the factory with identical MAC addresses. They work fine till you install a second one on the network. The solution was to install the drivers from SiS. This changed the MAC.

So check that you don't have conflicting MAC's

[Yuxi]

I never changed the network in any way before this happened. I installed a PCI network card, and it works fine now. But the computer now turns itself off frequently and the SB_POWER LED on the motherboard turns off. I go to the back, turn off the PSU, turn it back on. The LED goes on, then goes off again. I think the motherboard is dying. :(

Update: When I turn the PSU off at the back, the mobo power LED turns on then off again. Weird... :ninja: Maybe a capacitor broke or something? I heard a few faint popping noises before it completely stopped working.

[JustGeorge]

Hmm. strange. I'm having a similar problem, but I mostly get the popup bubble saying "a network cable is unplugged" It been happening every half hour or so for about a week now. Using D-Link Wireless Router model DL-524 and the built in Intel Pro 100/VE NIC on my D865PERL board. This computer is wired to the router, but just like you, my wireless laptop is fine. Its p***ing me off to no end. Heres what I've done so far:

1. Switched ports on my router to esure it wasn't a faulty port.

2. Reset router to factory defaults.

The only thing that has fixed it is romoving the router and jacking straight from the cable modem to the computer. Haven't had a lick of trouble since. Did anyone else read something about SP2 screwing up network connectivity where NAT is present? Here is the link:

http://zdnet.com.com/2100-1105_2-5321783.html

I'm not too savvy when it comes to networks, but I know my home netowrk is NAT. I don't know if I should return the damn router or what.

[JustGeorge]

Wanna here something funny? As I said, I jacked the modem straight into the computer. After a few hours of zero error operation, I decided to hook the router back up an roll back the firmware to see if that was the issue. The router has worked flawlessly since I hooked it back up! WTF!? I looked around in the settings and noticed a change. Before, Under the status tab, the DNS address listed in the WAN section appeared to be 2 DNS servers addresses ran together. Any attempt to enter these address under the Primary and secondary always returned an error saying they were invalid. The change is that now only 1 DNS address is there and it is valid as its the one I inserted under the Home/WAN tab. I had the DNS address in there before, but it still showed the 2 invalid address ran together. Hope that makes sense to everyone. Anyway, its trouble free operation now :) Perhaps you guys should check this as well.

[JustGeorge]

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[_R2D2]

I have the same problem.

Caboose447: does this always work? Any chance my internet won't work after this?

I have xp sp1 + a 3com etherlink xl card.