We asked our electrical pros what problems they run into with GFCIs and how to solve them. For starters, we found that most complaints occur when several outlets are protected by one GFCI. There are several possible causes, ranging from a light or appliance with a ground fault that's plugged into a downstream outlet, to a defective GFCI or even a circuit with too much cable. To determine whether the problem is with the GFCI itself, or downstream, turn off the power to the GFCI and disconnect the wires from the “load” terminals. Push the reset button (if it doesn't click, you'll have to reset it after the power is back on) and plug a GFCI tester into the GFCI outlet before you turn the power back on. If the GFCI trips after you turn the power on, replace it. If it holds, then the problem is with one of the downstream outlets. To avoid the timeconsuming process of troubleshooting the “load” outlets, the easiest and best solution is to replace each of them with a new, tamper-resistant GFCI.