pippi,

Have you checked with Microchip? They support their products well. Also, they sponsor a forum called

Programmers (PRO MATE II, MPLAB PM3, PICSTART Plus)

that is here

http://forum.microchip.com/tt.aspx?forumid=15

You might want to try there as well.

Questions -
Have you tried several 877A chips to make sure the problem is not a damaged part?
Can you program other 14-bit core PICs (e.g., PIC16F628)?
Is this a new problem that just developed with the 877A or have you successfully programmed them in the past?

Hopefully someone here will spot your problem as well.

Good Luck,
Paul Borgmeier
Salt Lake City, Utah
USA