Just to say Thanks to all who replied and offered advice on this matter.
I have now removed McAfee and installed AVG--and I have to say I am very impressed with the latter in every respect. In fact, the contrast could not be starker !.
My PC turns out to be clean--and the speed of the virus check was incredible--again, in contrast to McAfee--as is the display format for that matter--so I am a lot happier now than I was 24hrs ago.
Once again, it would not have been possible without the assistance of those on this site.
Best Wishes
K n C