Quote Originally Posted by MaxG
hi,
I can only program one time (from empty) any 18F4620 part. Next times it gives lots of fails in verification (the piece remains with the first code programmed unchanged). My warp13 can program with no problem 18F2620. Is there any undocumented knowing or trick for programming the 18F4620?

Thanks.

Try putting a pulldown on RB5/PGM. It sounds like your trying to use LVP and therefore need the pulldown. Check your LVP bit in the Warp13 software. Failing that, it sounds like you have a hardware problem like your MCLR* line isn't getting to the PIC correctly. I've been using the Warp13 on the '4620 for a couple of years now and haven't had a problem yet.

JDG