Hello,
I have a very annoying problem with a website called "Celldorado.com" at the moment. It started popping up regularly a few weeks ago and has consequently started all sorts of other websites popping up.
I have Spybot Search & Destroy, AVG, McAfee and Windows Defender, but none of them find any problems. I also use Firefox Web Browser and have manually blocked the various cookies that these websites keep adding to the computer.
Please God help me before I throw my PC out of the window! 
Your rated as an excellent forum, so I'm hoping you can help me out.
Thanks.