Laptop won't connect

My Dell won't connect to any wifi networks this morning, nor will it make a connection to the BT Hub3 by Ethernet. I have a built in Intel N adapter, which I tried all the usual steps with before disabling it and trying a BT N wifi dongle; no connection there either. The Hub is connected with an excellent signal but the laptop won't recognise it. All my other computers connect as usual so it's not a router or Infinity question. So I disabled my firewall and set IE9 to the lowest security setting - nada.
This is definitely an isolated problem on the computer and not the network. Just wondering what else I can try. The only thing I can think of is a System Recovery to yesterday, when everything was fine. Strangely, IPconfig reports all the correct addresses at ethernet and wireless, even though there's no connection.

Hi,

Does your laptop have McAfee Antivirus installed by any chance?

Yes! But I disabled the firewall and tested that aspect.

Hi, there was a problem with the McAfee updates last week - I suggest completely uninstalling McAfee, restart the system and you should have Internet access back - then you can download it and reinstall it...

Nice way to spend Saturday morning, thanks McAfee!

Edited by TechGuyUK (Sat 25-Aug-12 10:09:26)

In reply to a post by TechGuyUK:

I suggest completely uninstalling McAfee ....

Can you do that without the downloadable "Uninstall" tool from McAfee?

Dreadful IS anyway. Server-side ones seem to be good, PC ones far from it.

Hi, I don't know exactly what the OP has installed - but the general info about the problem suggests a simple uninstall will retore the Internet connection and you can go from there..

I wouldn't re-install it - much better to install Comodo IS http://www.comodo.com/products/free-products.php IMO

In reply to a post by TechGuyUK:

Hi, there was a problem with the McAfee updates last week - I suggest completely uninstalling McAfee, restart the system and you should have Internet access back - then you can download it and reinstall it...

Nice way to spend Saturday morning, thanks McAfee!

Is this problem documented?

Thanks for pointing me in the right direction. Yes, it's mentioned a lot if you Google McAfee+loss of networking or similar. Use the date filter for last month/week, as there are many items about this company's dodgy updates in the past. There's an article on their website too with complicated instructions about how to get out of it. Dell have also published a warning. So I'm paying nearly £50 a year to have my computer screwed - back to Norton, I suppose. (Now waiting for 50+ negative posts about the latter, but it works well on one of my oldest lappies; no hassles in 6 years, but it is very resource hungry).

I use MSE and Windows firewall because it's free. I have my network behind a router firewall and I don't have any hassles either.