PIC16F877A reprogramming failure using PICKIT2 programmer
You may have blown the PIC. This has happened to me with a PicKit 3 a few times. The PIC would heat up a rediculous amount while being programmed, so much so, you couldn't touch it. 

Try reading back the hex from the PIC and see if you get anything. If it does it with one and not the other then it will have blown. Didn't figure out what was causing it but you may want to look out for any shorts on your board.