Hi Catdaddy, I find forum operations not friendly for beginners and this was the only way I could find to reach you ( Ian061945 ). Thanks for you advice on trj.dealware. Twas not I who marked your answer as correct but I think someone called ex_brit.
However at the link you gave me Anti-Spyware/Malware & Hijacker Tools
the advice was to do a system reboot to a time prior to the malware arriving. This I did and it seems to have worked ... the computer seems to be working ok and the incessant message "ring this number and pay money to solve your virus problem" or words to that effect, no longer appears.
Please let me know if you believe the trj.dealware malware may simply have gone underground, requiring use of the further software that you recommended.
Thanks again, Ian.