Hi guys, and thanks for the replies.

Yes I did fit the 0.1uf capacitor as close to the PIC as I could (pins 19 & 20), as well as across the main power rails on the breadboard. The PG-02 programmer is connected direct to Com1 via a standard 9 way serial cable - no convertor is used.

The three '2550's were sample chips from Microchip, I've sinced tried one that I purchased this week from RS and that too shows the same issues, so my guess is that there is something the 18f2550's need (either physical hardware configuration, or software) that either my hardware or the software can't provide. Like I said the 16F873A programmed 1st time and works fine...

I'll have a look at the other chips you mentioned Steve, and maybe a few others. Just need to brush up on my rusty skills and try out some new things in PBP (LCD and A to D )

Whilst agree that after all these posts, and what has turned out to be a long thread we didn't actually resolve the issue, but I did learn from the experience and have a better understanding of what to lookfor and how to edit INC files etc. I just hope that others can also learn from the topics covered in this thread too.

Thanks for your time and input