Hi Bruce

Problem solved!

Your download produced the same symptoms as my programme, but when I read it back it certainly didn't show INTOSCIO - from memory it might have been INTRC also MCLR was ON. Obviously not picking up the correct config settings as you suspected.

I had a lucky flash of inspiration and in Microcode went to Options||More Options and pressed Set Options to Defaults.

Immediately all came good and the PIC programmed perfectly.

So thank you (and thanks to the others) for your help and I can get back to my PCB testing.

I have no idea why my Microcode would not be locked solid onto its defaults. Maybe I hit something by mistake. Also would you know what parameter stopped this from programming correctly?

Useful to remember to check in future and would save 24 hours of hair tearing......

Regards

Adrian