I recently came across a situation where there was a row of outlets that had stopped working. One day they all worked then the next the outlets did not work.
The first thing to check is the breaker. The breakers for 120 volt outlets will be the small breakers in the breaker box. This is most likely in the garage or laundry room. A tripped break will have a small reddish colored window near the switch when it is tripped. All you have to do is push the switch towards the outside of the box or the off position then push it back to towards the inside of the box or to the on position. Most of the time this will take care of the problem.
In the event that there was not a tripped breaker or this did not solve the problem. The next thing to try, is to locate the GFCI outlet on that circuit that is not working. This will be an outlet that has two small buttons in the middle of the outlet. Be forewarned, sometimes these can be very difficult to locate. They could be behind furniture, outside, in the garage or basement, etc. But it is important to find the GFCI outlet on the nonworking circuit. Sometimes it may help to get a small plug in light, like a night light and start plugging it in to every outlet. You should notice that there will be a “string” of outlets that are not working. The outlets are wired in a daisy chained, the first outlet connects to the second, the second connects to the third and so on. Typically they will all be on the same wall or in a shortest distance sequence, since the wires should run on top of the wall in the attic.
Once you find the GFCI outlet, press the test button and this should trip the circuit. Then press the reset button and this should solve your problem.
If the outlets still do not work after resetting the GFCI outlet. The next step will be a little more difficult and that is to check the GFCI outlet and back-stab wiring on all the outlets that are not working. These are the wires the a pressed in to the back of the outlet. Before you begin make sure you have turned of the power. Since these outlets are not working, it is best just to shut down all the 120 volt breakers or you can throw the main switch which is the really big breaker at the top of the box. If you are NOT 100% certain that you have shut off the power, call an electrician.
Once you are certain the all the power is off find a known working GFCI outlet and replace the one that was not working. Tape off the bare wires from the box that the known working GCFI outlet came from. This will insure that you do not short the wires when the power is on. Turn the power back on and check if the outlets are working. If that fixes the problem you will need to get another GFCI outlet from you local hardware store to replace the now vacant outlet.
If replacing the GFCI outlet did not solve the problem turn the power off again and then you will need to start taking the other outlets apart and check each of the wires in the back. Start at the outlet that is closes to the breaker box and work your way away from the breaker box. At some point you will find wire that has pulled out of the back, broke, or a broken outlet. If this is what you find push the wire back in the back-stab or replace the outlet.
Once you have all the outlets back together turn the power on and check the outlets. At this point if the outlets still do not work there could be a broken wire in the attic and it’s time to call an electrician. There is nothing fun about working in a attic. Not to mention you will need test equipment to test the wires and breakers.