Only a Dell Laptop does not connect to the Internet

I have Sky broadband at my home and everything was working perfectly till yesterday.

I was able to connect wireless ly to the internet. Yesterday, my main laptop started showing an Exclamation (!) sign on top of the signal strength indicator. On mouser over, it says "Unidentified Network". However, all my other laptops were still connected to the internet.

Even the same laptop when I boot in Ubuntu works fine. I have tried disabling and enabling the Network adaptor multiple times but nothing changes. On the laptop that works, I logged onto the router interface and it shows the non working laptop as connected but it shows it as "Unknown".

Can anyone please suggest what could possibly be wrong? I checked the TCP/IP settings and they are same across laptops.

Aditya Sehgal

Posted 2012-08-20T17:03:32.313

Reputation: 163

Answers

Type this is command prompt:

netsh winsock reset

"Enter"

shutdown -r -t 0 /F

This should repair the IP bind. Let me know.

r0ca

Posted 2012-08-20T17:03:32.313

Reputation: 5 474

Hi rOca, Tried the above but the issue still persists. Though, the mouseover now says "No internet access". Earlier, it was saying "Unidentified network". – Aditya Sehgal – 2012-08-20T17:16:30.937

Did you try to reconnect to the WiFi SSID? Use the Dell software to reconnect instead of Windows one. Let me know if this is successful. Thanks. – r0ca – 2012-08-20T18:54:58.660

hi. its just not wifi. Ethernet doesn't work either. I tried connecting to WiFI SSID too but doesn't connect. My dell software didn't came with any software to connect. I have always used windows and it always use to work – Aditya Sehgal – 2012-08-20T22:51:22.803

If you go on the Dell website, over another PC, you might find a Wireless driver that also should come with a connection wizard. That could help. Also, I would try some other stuff like reinstalling the device driver, trying to connect with another user's session or even, try with a Wireless USB adaptor. The last thing I'd do is to reinstall from scratch... long shot tho. – r0ca – 2012-08-21T13:17:47.910

@roca : have tried almost all of the above (except for Wireless USB adaptor thing). In some other thread, there is a mention of McAfee recent update causing this. Therefore, I tried system restore but still stuck. Am running out of ideas. One thing I did try was to run wireshark and could see dhcp/arp msgs going but nothing else. Sometimes, i see icmpv6 messages going too. Do you think my ip stack is fried? – Aditya Sehgal – 2012-08-22T11:12:14.580

That could be possible if configured. Can you disable IPv6 if enabled? And to redo the stack, it's the command in my answer. I thought that would do it but I'm sorry none of my solutions work. – r0ca – 2012-08-22T13:13:32.440

@rOca : It has started working and I am not sure what I did. I was still suspecting McAfee therefore booted my laptop in safe mode. Sure enough, it started working so i thought McAfee would be the problem. However, then i logged in normally and it started working without me doing anything :) – Aditya Sehgal – 2012-08-22T19:46:32.757

Did you change anything related to McAfee? Updates? – r0ca – 2012-08-22T20:31:06.700

@rOca : no nothing. would sure like to know what went wrong – Aditya Sehgal – 2012-08-22T20:55:41.307

Glad you can now connect :) Take care. – r0ca – 2012-08-22T21:18:02.173

Well, all your other network devices are connecting just fine so it's not the AP or your internet connection in general. It's also not likely the hardware because the same laptop works under Ubuntu. My guess would be wireless drivers. Look in the Windows Device Manager to see if there are any new "Unidentified Devices". If there are, then that unidentified device may be your wireless card.

You could try uninstalling and reinstalling the wireless drivers. Dell has a pretty good driver database where you feed in your service tag and it will give you all the drivers for that laptop.

Green

Posted 2012-08-20T17:03:32.313

Reputation: 556

Even the ethernet doesn't work. I checked as you suggested and there is nothing out of the ordinary. Just to be safe, I un-installed and re-installed drivers but nothing has changed. – Aditya Sehgal – 2012-08-20T23:46:13.860

The odd thing is everytime it seems to get an IP address. The IP of the DHCP server is also the same as the Gateway. The laptop can get an IP yet cannot talk to the Gateway when I ping it. Running wireshark, I can see arp packets flowing but don't see any ICMP message – Aditya Sehgal – 2012-08-21T00:02:24.610