This is an update with, first of all, thanks to Herman for his recommendations. However, I followed the YouTube tips and various other on-line remedies but failed - I put it down to my having had an IT bypass but Sony could make this so much easier if they put a bit of effort into it. Having put myself through the mill with no tangible result I did what I should have done in the first place - delegated the job to the kids, all of whom are in IT related positions of one thing or another, and within half an hour my problem was solved along with the reprogramming of the remote control - don't ask me how because I have no idea except that they are now my default go-to resource and so I will get them to do the same on my other older Sony TVs😎
