I hope someone can help! I recently bought a VR2800 for use with TalkTalk Broadband, which worked fine. I was then upgraded to Fibre and couldn't get it to connect at all. After several hours of fannying around I gave up and plugged in the free TalkTalk model.

I decided to give it another go this morning to see if I could find the issue. I couldn't so plugged back in the TalkTalk device. However, now I cannot access the internet at all from my PC. The modem is working fine, as I can connect via wireless, but my PC Win7 can't connect at all. I have an "unidentified network", "Local Area Connection doesn't have a valid IP configuration" issue, which I have been unable to fix using all the advice found online. I have even tried a system restore with no joy.

What has happened? Why did plugging in the VR2800 to my PC cause the network settings to get screwed? How do I fix it? And once I have, how do I get the VR2800 to work?

Thanks you for any help given!