Help Please!!!!!

i am beginner in programming pics the pic i want to programe is 16f877
the programmer i am using is pickit 2,

i successfully programmed my first led blink program and avery thing went well,
but when i wanted to do a led scorrling programe the 16f877 didint work, so i returned to the led blink programe and it didnt work also there is no output at all on the port b pins

i am using 4mhz crystal

4.7k resistor on pin 1. and 5 volt supply

i am doubting that my pic is dameged,
i also tried the other ports but they are all at 0 volt.

Load your LED blink program & check your config setting You must enable MCLR = ON.Build it once & see.