At last ! Back on line !
Desktop having a noisy graphics card replaced so I brought down my laptop which has worked perfectly for 7 or 8 years now.
Thinking that it hadn't had a good clean up in a while I downloaded and ran SuperAntiSpyware which I've used on the desktop for a couple of years.
It found 3 trojans and a couple of file entries which it recommended I get rid of,which I did. It also said that to be sure I should reboot so I did.
It then came up with 'This copy of Windows needs activating.' By phone and internet it won't do it saying that I may be the victim of hooky software. I most certainly am not.
Any ideas what occured and how I put it right?