Blown Fuse or Tripped Circuit Breaker

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  The most common explanation--and the easiest to check--is a blown fuse or a tripped circuit breaker. Check the main circuit box and any sub panels that may need attention.
  
  

Ground Fault

• GFI outlets have a test and reset button. Monthly testing is reccommended.
  
  Circuits outdoors, in kitchens and in bathrooms are often protected by a separate type of circuit breaker called a ground fault interrupter, or GFI, that can be built into one of the outlets in the room. Check all the outlets in the room as your non-working outlet to see if they have a GFI that needs to be reset.
  
  

Safety

• Blown fuses, tripped breakers and popped GFI outlets are often signs of larger electrical problems. If any of these safety devices is repeatedly triggered, investigate for other problems on the circuit such as short circuits or overloads. If trying to make repairs yourself, make sure the power is turned off to the circuit before working on the outlet.
  
  

Loose Wires

• Occasionally wires on outlets become loose or disconnected, especially on outlets that are not firmly mounted. If the outlet moves easily side to side, or works intermittently, turn off the power and check to see of wires need tightening.
  
  

Broken Wires

• Wiring can also become brittle and broken if flexed or pulled, especially in older homes. This problem requires the same fix as a loose wire--turn off the power and inspect the wire at the failed outlet.
  
  

Worn Socket

• Electrical sockets sometimes become loose internally and fail to make contact when something is plugged in. If you find that wiggling the plug makes something work in the socket, consider turning off the power and replacing the outlet.
  
  

Broken Socket

• Despite having few parts, outlets sometimes simply break, especially older models. Turn off power and replace the outlet.