Using MPLAB, GOOD!

First:
Turn off the setting of the fuses in your programmer software and do it in code or the *.inc file.

Second:
To make this all digital use
Code:
ADCON1=7
CMCON=7
Third:
Try this code before you write something "looooong", just to make sure everything is working.
Code:
'****************************************************************
'16F877A       HEART_BEAT
    DEFINE OSC 4
'####################
    @ __config _XT_OSC & _WDT_OFF & _LVP_OFF & _CP_OFF &_BODEN_OFF
    ADCON1=7
    CMCON=7
    
START:
    HIGH PORTD.2
    PAUSE 100
    LOW PORTD.2
    PAUSE 100
    GOTO START