I was helping a friend replace outlets in his old house. The original outlets have two wires and no ground. They are mounted in a metal box. We installed the new 3 pronge outlets and used grounding pigtails to ground them to the metal box. We turned the power back on after completion and none have power. We flipped all the breakers being we were not sure which breaker powered that room(we killed the Main when we did the work). Any ideas why no of the outlets work or switch in the room works?