Richard,

Thanks for the prompt reply.

In some ways it is a relief to know it is not the code. That is a big step forward.

As per my first post I had tried two different programmers, both from the same origin. I also tried an older version of MPLAB (which I had had programming success) and a download of the latest version. No success with any combination.

I shall wend my way carefully and methodically through re-installation and settings again, including trying the job on the (retired) 32 bit PC that previously yielded success. All while I wait for delivery of a new programmer I ordered on suspicion.

I really am getting too old for all this. In retirement things are supposed to go smoothly!

Thanks again for your help.