Tonight I experienced a strange network problem,

I found myself unable to connect to my Win7 Media Center,  from anything I tried.. all the remote management tools I used didn’t work and not even remote desktop. The machines IP responded to ping fine but I could not resolve the DNS name of the machine which was weird, what was weirder was that I had just been using the machine few hours before without a problem.   I couldn’t sleep anyways so I grabbed the extra keyboard and mouse I have on hand and started debugging the problem.

The machine got an IP from the router, same one it always had,  it could access the internet just fine and the rest of the network so why couldn’t I connect to it?.. everything seemed fine until I went to the Network and Sharing center,  the network was suddenly unidentified and the profile used was Public which is rather restrictive as it should be.  I found myself asking myself (I do that quite often) why I had suddenly missed contact with the Homegroup. So I tried all the basic troublesolving things I could think of ..

  • restarting the computer, that usually solves all my problems :)
  • releasing and renewing the IP
  • disabling ipv6 and running only with ipv4
  • uninstalling (and deleting the driver) and installing it again (with reboot inbetween)
  • set a static ip4 address, this seemed to solve the Homegroup problem but I was still listed as not connected to the internet..
  • cleared the arp cache
  • flushed dns cache
  • deleted the client configuration from my router
  • checking for in the route configuration which wasn’t there (corrupt route,  if was there all I had to do was delete it, but since my route was normal this didn’t fix anything)
  • restarting the router
  • checked for viruses or rootkits (unlikely but you never know)
  • .. And probably bunch of other things that I can’t recall

Nothing solved the problem completely,  I had been working on this for over an hour at this point so I gave in and hit Google to look for solutions to this,  and found couple of possible solutions that I hadn’t thought of or knew caused problems such as

  • Apple’s Bonjour can apparantly cause problems similar to what I was having,  but Bonjour wasn’t on my machine so no luck there
  • Some people found that the SSDP Discovery Service wasn’t running which caused similar problems for some,  but SSDP was running for me so no dice.
  • Resetting the winsock catalog fixed it for others but not for me.  To reset it you run “netsh winsock reset catalog” under administative command prompt and then restart.
  •  I even tried a dhcp fix described here , it didn’t work but it was a farfetched idea to begin with.

This was getting on my nerves,  nothing I tried worked and I was getting pretty tired and was thinking about hitting the sack and catch some sleep when I found this article, . Changing the NIC’s MAC address seemed to solve this for many people so what the hell,  couldn’t hurt trying it,  After changing the MAC Address everything worked,  (instead of entering a bullshit address like suggested I just copied the NIC’s original MAC Address and changed the last digit). I found the Homegroup instantly,  internet connection was reported correctly and everything works as it should.  Stupid problem 0, Joe 1 :)

One Response to Unidentified Network on Windows 7

  1. Steve says:

    Just a related note, I ran across this issue a year or two ago and was able to specifically track it down to performing an update to the virtualization software “VirtualBox”. Due to it uninstalling/installing the virtual network adapters, it shifts your computer to public firewall settings because it doesn’t trust the new virtual network and takes a conservative stance. Like you, I run WMC w/ extenders and it’s immediately apparent when you can no longer hit the machine up for services or even RDP into it because of the firewall shift. No clue if this was your cause, but I definitely noticed the exact same symptoms.