How to Troubleshoot a Computer

by Contributor

Before calling technical service and paying for "help," take a look at your computer yourself. A little common sense may help you solve simple hardware and software problems.

Restart the computer. Many software problems will correct themselves when you do.

Check your cables. Keyboard not working? Make sure it's plugged in. Mouse not responding? Make sure it's plugged in.

Check the electric power. Plug a lamp into the same power outlet that's connected to your computer to make sure the outlet is working.

Make sure the computer and monitor are plugged in.

Disconnect peripheral devices (such as a printer or external Zip disk) and restart the computer.

Listen for unusual sounds. Is the cooling fan running? Is the hard drive making noises?

Look inside the computer for wires that aren't plugged in all the way or other faulty connections.

Start the computer from an external start-up disk, such as the system software CD that came with your computer.


  • check If you do decide to call technical support, write down the exact problem and what you were doing when it occurred. Also note any error messages. Try to replicate the problem if you can.
  • check Be as specific as possible when talking to the support person. Example: "Whenever I try to start up my Mac, I see an icon with a little question mark. With my iMac CD, though, the computer boots normally."
  • check Computers tend to crash or hang when their hard disks become too full. Free up space by deleting unnecessary files and emptying the Trash or Recycle Bin.


  • close Don't zap yourself or your RAM. When working inside the computer, turn the power off but leave the electrical cord plugged into the surge suppressor. Ground yourself by touching the casing of the power supply before touching any of the computer's circuits.

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