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I have a cable modem from my ISP to which I can only connect wirelessly.

Currently I have a desktop PC(windows 7 x64) a dell laptop(windows 7 x64) an iPod(iOS 3.1.3) and a linksys wrt54g router (v8 with dd-wrt)

Laptop and ipod behave as expected. They get an IP that stays mostly the same. for example & My desktop PC does not have a wireless card so I wired it to the linksys router. The router is configured as follows (as outlined in the help & tutorial pages):

  • Wireless mode: Client Bridge
  • SSID and wireless security is configured exactly as in the ISPs modem
  • DHCP is disabled
  • fixed ip address

At first all seemed OK. But then I started to notice that the desktop PC could not be pinged with the hostname. Only by IP.
I then noticed that the desktop IP address would change even though the computer was not shut down. Not even it's IP released/renewed. Sometimes it changes every few minutes. sometimes after a few hours and other times not at all for the whole day. It keeps adding up. So if the ip was it would then be now it's at .0.100. It is a problem since connectivity is lost while transferring files, streaming, shared folders, etc.

I suspect it is the routers fault but I don't know where to start looking to correct this issue. Any help or pointers are appreciated. Thanks!

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Without logs (from the router) to shed light on why it's happening in the first place, I'll describe what should be the simplest fix and also help troubleshoot a possible cause.

You can set a static IP address on your desktop; under the network adapter settings for IPv4, switch from "Automatically Assigned" to an manual, and set your IP to an unused IP (something like Set your subnet to you and gateway to your routers IP address. You should also be able to set your DNS servers to either your routers IP, or a public DNS service (Google provides this @ and

If you continue having issues after you do this, I suspect you have a bad ethernet cable, ethernet card, or port on your router.

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Thanks for your help! I changed to a manual ip and it didn't work at first. I had to replace the ethernet cable and then I had a working network. The pc is still not pingable via hostname. If I switch back to automatically assigned IP the old behaviour returns. Every few minutes a new ip-address. What do you need to know more about the problem? Thank you again! – leugim Aug 18 '12 at 5:28

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