My door won't close or go's a few inches stops and comes back up.

• Openers sometimes have infra-red sensors that mount on either side of the garage door a few inches off the floor.
  
• Check that they can "see" one another. If they cannot the opener thinks there is something in the way of the garage door and will not close.
  
• Make sure the wires that go to the back of the sensors are not broken.
  
• Make sure bugs have not made a home in the lens part of the sensor. Here in Texas mud doppers love to put mud in these lenses and make a home of them. Spiders also like to build webs or even leaves blown in from outside can cause the infrared to malfunction.
  
• Make sure they are not in shock. Voltages higher than normal, like lighting storms and power company voltage spikes can "shock" an infra-red. It will cause it to not work and not allow the door to close.
  
• The garage door itself can have problems also that can prevent the door from closing properly. It is just a reminder to check the safety beams to be sure that this is not the problem. Routine maintenance would also be recommended to ensure proper garage door function.