Take the 18F2550 out of the socket.
With the pickit 3 connected to the board, open the software and tick the VDD on box under the Microchip symbol.
Measure the voltage between the VCC pin and GND on the board - it should be very close to 5V.
Then tick the MCLR box and measure the voltage between the MCLR pin and GND on the board, it will be either about 9v or 12V - I forget which it is for the 18F2550.
If those voltages are there then it's a case of following through to the socket to make sure those voltages are on the correct pins for the PIC. 5V should be on pin 20 and MCLR voltage should be on pin 1.
With the pickit 3 connected to the board, open the software and tick the VDD on box under the Microchip symbol.
Measure the voltage between the VCC pin and GND on the board - it should be very close to 5V.
Then tick the MCLR box and measure the voltage between the MCLR pin and GND on the board, it will be either about 9v or 12V - I forget which it is for the 18F2550.
If those voltages are there then it's a case of following through to the socket to make sure those voltages are on the correct pins for the PIC. 5V should be on pin 20 and MCLR voltage should be on pin 1.