Joe, Many thanks for the very interesting link.
Emgee, I had a screen appear that suggested itself to be a windows security alert, warning me of a virus attack(3of them) and listing them, with the information that my operating system was in melt down. Action was advised to immediately use a scan (free of charge) by downloading from the page.
Ran windows security scan and Malwarebytes both gave clear result. The initial screen was quite convincing, take care.
Paul..