Question Author
Thanks for the good advice - I had only removed McAfee using the Windows removal tools which I thought would be enough! However, following your instns I downloaded the Free McAfee removal tool and did that.
Next I downloaded Free Malwarebytes from their own site and it took 27 mins to search thru and ended up with 41 items (mostly Registry faults) which it quarantined.
Hope this is all ok now and thanks again.