ip address issues

Hello folks,

1st off what an excellent forum and resource. Always come here to look up probs with w7.

Here is my problem. w7 seems to be holding onto my IP address and causing probs. let me explain further. Say I connect to network A and I am assigned an address from a DHCP server (I have no idea what underlying technology is supplying the IP address). then I go home and connect to my home network. Now at my home "network b" gives me another dhcp assigned IP address. I connect fine with a valid address.

If I return to network A the only way I am able to pickup a new IP address is by going to the command prompt and doing a release and renew. It doesnt matter if I am coming out of hibernation or booting up fresh, it always picks up the last IP address it had, which in some case may be already re-assigned elsewhere causing a conflict.

I have the latest service packs and OS updates as well as the latest drivers for my nic card. The problem only seems to occur when I connect to my corporate network. Any thoughts?

thx for the reply and bummer you have to live with that too. just to clarify i am pretty sure this doesnt just happen on resume from hibernation. it also happens when booting fresh. to me it seems like the ip address is being saved somewhere in the reg and next boot it just comes back with the same, regardless.

Hardware info - laptop dell latitude 6510 and nic Intel(R) 82577LM.

It's working the way it's supposed to, sort of.....

Your laptop, as the client, is requesting a renewal of the IP it was last assigned, which it's supposed to do. Your DHCP server at work either fails to "hear" the request or fails to check to make sure the IP is available.

You say it works fine when you go home from work, so all of the devices involved are working just fine there.

Talk to your IT folks at work. See what they suggest.

Meanwhile, change the subnet of your router at home so the IP it remembers isn't even available on your work network, assuming of course that you want to go to that much trouble.

I had a laptop running XP some time back that always did that. Annoying behaviour, but nothing I couldn't work around.

Another thought, from the redneck side of my brain; Create a batch file with "ipconfig / release" in it and run it before you shut down, or even put a shortcut for it in startup.

TCG said:

I'd love to hear the solution to this, our laptop users would love to not have to restart every time they come back to their docking station.

In your case, have them unplug the network cable for a few seconds. Sometimes that works.

A batch file like this:

ipconfig /release
pause
ipconfig /renew

Might be a better solution than rebooting since it would take less time.

yeah pricetech thanks for your reply i do appreciate the info - however i understand dhcp and also nobody else at my office has this issue across various operating systems, so i believe the problem to be specific to my w7 build.

let me clarify this a bit further and also bump this back up to the top

so i was just connected to my corporate network, which is a 10.x network. I updated some software which caused me to reboot. Upon reboot when windows reloaded it decided to use a 192 address again instead of the previously assigned 10.x address. I did a release and renew and viola all is good again.

greta suggestion matt however that address that my w7 box keeps reverting to was not assigned from my home network.

it happens intermittently but fairly consistently. i am guessing i can see if i can search out that IP address somewhere in the reg and delete the associated keys. unless anyone else has more good ideas i will do that next time this pops up.

davewave said:

so i was just connected to my corporate network, which is a 10.x network. I updated some software which caused me to reboot. Upon reboot when windows reloaded it decided to use a 192 address again instead of the previously assigned 10.x address. I did a release and renew and viola all is good again.

That's a horse of somewhat different color then. Sorry if I misunderstood the original post.

Nothing comes to mind as a cause or solution, but I'll keep it in mind and maybe I'll come up with something. I think your trip through the registry would be worth a try.

Let us know what you find.

Hi Dave, did you manage to solve the issue.

Thanks