Having a strange problem that I found after my wife overloaded one of the circuits and tripped a breaker. After finding the shorted wiring and replacing, the breaker now stays in the on position and all recepticals/fixtures on the circuit are receiving power. But at one outlet I cannot get any power through the plug when it is touching/screwed into the junction box. If I pull the outlet out of the box to where it is not touching the metal junction box the outlet works fine. This is the last box on one branch run of the circuit so there is only neutral and hot coming to the box (bx cable with out separate ground wire) and no wiring leaving the box. I have tried replacing the outlet with a new one to eliminate the possibility of the faulty unit but the same issue exists. I have also added a separate wire to connect the ground screw on the outlet to the junction box, but this did not have any effect. Any ideas on what might be causing the problem and/or how it can be fixed would be greatly appreciated.