Assuming that went ok and you got a yahoo page now goto each of the two network adapters in turn an for each one go to proprties, scroll down to internet protocol version 6 (ipv6) and uncheck the box next to it. Apply and exit.
Now the wireless adapter is showing disconnected with no IP address again! I don't think we are far off and I'm sure the underlying problem was ipv6 but it's gone 2am here and I must get some sleep! I'll check in tomorrow.
Alright. Thanks for staying up so late to help me.
Update : My bad. When I rebooted the computer, my wireless connection to the router was forgotten and I never noticed until after your reply. This is the actual ipconfig /all as the previous didn't had the wireless connection on.
I'm back online so when you get on we'll see if we can finally nail this - I'm certain it's IPv6 that was at the root of it with the lasck of IP address allocation to the wireless connection clouding the issue. See you later abw.
Update : I tried reinstalling winsock but there is no change. Issue still persists. After all this, there is definitely nothing wrong with the router but there's an unknown issue with the way my laptop receives network infomation. My D-Link router required no firmware updates. Neither did my laptop's network adapters. There was no messing with the registry until just now and still, nothing changed. I tried reinstalling my network adapters then immediately troubleshooting to see if anything could be picked up. But as usual, there is no change.
I have a suspicion that one of the Windows Updates have caused this issue. Possibly an update which was meant to aid in the internet connection or improve it.
Since the last update, this issue could not be solved with ipconfig commands anymore. So its possibly KB3000850. Of course its all just suggestions and there's no real proof even if several evidences lead to here.
Because the same update was installed on 25/11/14, which was the day I first received this issue, I can only think of this update as the culprit. But I'm no computer expert...
Update : Yep! FINALLY! Solved it. Windows 8.1 Update KB3000850 is the problem. I got it uninstalled and I could access the internet again. Thank you for helping me through this issue. I've learnt several things I would never learn if this issue never appeared.
Well done and thanks for the feedback - these things usually come down to slow methodical detective work and logical deduction - Sherlock Holmes would have been proud of you. Just need to ensure that you don't have updates set to automatically install and if and when it reappears yo ensure that you hide it.