What to do about tail lights not working

RE-CHECK ALL CONNECTIONS... USE A MULTI-METER TO PROBE FOR 12 VOLTS AT EACH LIGHT BULB... FOR STARTERS. DO YOU HAVE VOLTAGE? IF SO... THE BULB IS BAD... EVEN THOUGH IT WAS PURCHASED NEW. CAME ACROSS THAT MANY TIMES. CHANGE IT AND CONTINUE ON THROUGHOUT YOUR ENTIRE PROBLEMS WITH THAT SCENARIO. IF YOU CANNOT PROBE FOR VOLTAGE... ASK A FRIEND TO HELP YOU DO THIS. GREAT LEARNING EXPERIENCE! OH! CK TO MAKE SURE U HAVE NOT INSTALLED THE BULB 180 DEGREES OUT! IT HAPPENS. DOES NOT MAKE CONTACT... CK IT OUT BROTHER...