How can I fix my Windows XP "Limited or no connectivity" error when I plug my laptop into my university network?

October 4, 2006 6:06 PM

How can I fix my Windows XP "Limited or no connectivity" error when I plug my laptop into my university network?

I've been plugging my laptop directly into an ethernet connection for over two years. Suddenly last week, I get a "Limited or no connectivity" error whenever I try to connect to the network, and now I can't access the Internet or anything. I didn't change my system at all. I updated to SP2 months and months ago, so I don't think that's the problem. Whenever I click "Repair," my computer cannot renew an IP address. I tried the Winsockfix and Microsoft patch 884020, but nothing has worked. I also uninstalled ZoneAlarm and checked for viruses and adware, but nothing's shown up.

Can someone be my new savior and help me out? I've spent hours on this!

posted by jordanian2 to computers & internet (12 comments total)

Can you connect somewhere else? Another port\area.

Can other people connect properly from that specific port you're connecting to?

If no to first, troubleshoot your pc. try cmd prompt: netsh int ip reset log.txt
If yes to first, no to second, connect somewhere else.
posted by PowerCat at 6:28 PM on October 4, 2006

I second trying a different port (and getting someone else to try the troublesome port), although I suspect this might just be that windows has thrown it's TCP/IP stack out the window, which has happened to me before.

Basically, your machine is no longer getting an IP from the DHCP server. I guess you could see if you can get a static IP (talk to the helpdesk), or you could even find out the IP range and just set your own static IP (ie. ask someone else what their IP is (you can get it via ipconfig from the cmd prompt) and then set your own IP to something similar (like, if there's is 10.1.1.50, then set yours to 10.1.1.75 and see what happens). The only problem is that if someone else has been given 10.1.1.75 by DHCP, then it will clash and not work (but windows tells you if this happens)).

One other suggestion is to try a different ethernet card. Easiest way to do this is to get a USB Ethernet device, although a PCI card is probably cheaper is you are confident to open the case. You can also try a Linux LiveCD, which would tell you if you windows installation is borked.

Otherwise, I'd start thinking about reinstalling windows. :(

Or, of course, just buy a Mac! Steve Wozniak is a member of AskMe now, so it should be easy to get your questions answered! Woot!
posted by ranglin at 6:59 PM on October 4, 2006

My university requires a VPN connection to connect via WiFi (dunno about ethernet, never tried.) Is it possible that they rolled out such a requirement?
posted by SteveTheRed at 7:14 PM on October 4, 2006

I have to ask: is there a chance your university has banned your computer from the network for any reason? I'd bet the likelihood that "Windows has thrown its TCP/IP stack out the window" is pretty low; that just doesn't happen randomly.

One way to test this: try another ethernet adapter, as ranglin suggested -- see if someone has a USB adapter you can try out. That brings with it a new MAC address, and new rules when it comes to network access.
posted by delfuego at 7:17 PM on October 4, 2006

Also, have you called the help desk? The IT department may have intentionally disabled that port and would have a record of that.
posted by MikeKD at 7:33 PM on October 4, 2006

hTree other suggestions you didn't mention that are kicked around on Usenet and elsewhere as possible solutions to your problem are:

Download and run the LSP-Fix utility.

Run the following command (NB: only works for XO SP2, which you have): netsh winsock reset catalog

Uninstall and reinstall the NIC drivers, as they may have been damaged.
posted by mdevore at 7:44 PM on October 4, 2006

Or they may have intentionally disabled your MAC address - either specifically, or as an effect of implementing a whitelist for the MAC addresses of all the campus computers.

Or you may already have been given a fixed IP address two years ago, and now they've changed the university network to a different IP subnet.

Or the switch you're connecting to could have become disconnected from the rest of the network, including the DHCP server.

Talk to the help desk.
posted by flabdablet at 7:55 PM on October 4, 2006

Yeah, talk to the help desk. If you were at the university I work at, those symptoms would most likely mean that our intrusion detection system had detected virus/worm activity coming from your MAC, and blackholed it. It could also mean that the subnet you're plugging into is saturated, and there are no IP addresses for the DHCP server to give you. Either way, that's something you'd have to talk to the help desk to resolve.

And if it's not one of those things, the helpdesk should be able to recommend most of the troubleshooting tips that have been mentioned here.
posted by hades at 9:02 PM on October 4, 2006

Do NOT reinstall Windows as suggested above. Speak to the helpdesk - it's probably port security.
posted by kenchie at 11:11 PM on October 4, 2006

Having never stayed in a dorm room, I didn't even think about the MAC address being blocked for some reason..

I agree wholeheartedly that you should contact the helpdesk before doing drastic things like reinstalling windows... :)
posted by ranglin at 1:15 AM on October 5, 2006

if you've been connecting for 2 years and all of a sudden you are running into issues, its most likely an external issue.

Have you broken the schools terms of service... running servers, bittorrent, excessive downloads, etc? Most networks will automatically cut you off from the network if you do that.

Another thing is that it could be a MAC address conflict with another computer on your network. (I've seen it happen lots of times). Try with a different ethernet adapter.
posted by mphuie at 1:35 AM on October 5, 2006

WIN + R
CMD
ipconfig /flushdns
ipconfig /release all (or name of connection)
ipconfig /renew all (or name of connection)
ipconfig /all (view to see if it worked)

Should work.
posted by eleongonzales at 8:42 AM on October 5, 2006