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treysha
01-08-2007, 01:49 PM
Hello,

I am facing a desperate problem, hope someone can offer some expert insight.

I have about 50 PCs in my LAN, all XP Pros running Dynamic IPs. Recently (about two weeks ago), one PC got disconnected from the LAN (while actively in use) with the onboard NIC showing "Limited or no Connectivity".

On client PCs side
-Checked AV, shows updated one-day ago, last scan a day ago was clean.
-Ipconfig /all shows a 169.xxx.xxx.xxx IP which tells me the NIC hardware part is working fine.
-Ipconfig /release can actually release the IP to 0.0.0.0.
-Ipconfig /renew got hung for a while before an "DHCP server not contactable/available" error appears.
-Doing Ipconfig /release and then /renew on another working machine proved that DHCP server is indeed still working fine.
-Installed another NIC on PCI, it was detected by Dev Mgr but still cannot grab any IP. Setting a static IP for the NIC still showed "Limited or no Connectivity".
-Installed a Wireless Adapter (USB), still cannot grab any IP.
-Did a ipconfig /flushdns, didn't help either.
-Downloaded a patch from Microsoft for "NICs giving Limited or no Connectivity errors", didn't help at all.
-Tried downgrading from Domain to Workgroup, can downgrade but cannot upgrade to Domain again - "Domain controller not found" error. But other machines can see the Domain just fine.
-Unplugged the PC from the network, set it aside for servicing and the next day, VOILA! everything works again! Even the onboard NIC now works.

Two days later, another machine showed the EXACT SAME problem. Set it aside a couple of days, and everything sorts itself back again.
A couple of days later, yet ANOTHER machine showed the same problems. Altogether, FIVE machines have given me the same problem, the last one has been down since four days ago and has still not rectified itself.

On the Windows 2003 Server side
-Checked Event Viewer on server, showed no errors on DHCP server.
-All machines are on different switches, so that rules out a switch problem.
-Restarted DHCP server service, to no avail.
-Restarted Windows 2003 Server, still the problematic PCs refuse to get connected.

Can any one please offer some advice? Network connectivity is everything in my LAN. One by one my PCs are crumbling.

treysha
01-08-2007, 01:55 PM
Just to add that when I "set the machines aside for servicing", I practically put the machines away and DID NOT do anything to them. When I get back to them to start further servicing works, the problems appeared to have resolved by themselves!

Any offer of advise is Greatly appreciated.
Many thanks in advance.

Erik
01-08-2007, 08:12 PM
How does the DHCP scope look? Might just be not enough IPs to go around.

Scerzilla
01-09-2007, 04:19 PM
this has happened to me on my home network twice over the past year, i just left the computers alone for a few days and then hooked them back up and they were fine again. i never could find an answer to why they were doing this!