Computer connections are open to contact with the air. This permits dirt to create short circuits and make computers useless. For example: My computer at work suddenly stopped working. It ran, but the mouse and keyboard did not work. Booting did not help. Both the mouse and keyboard connected directly to the mainboard. Time for a new mainboard, right? WRONG!

Time to clean out the dirt. Often compressed air or the canned "Dustoff" stuff works. In this case, these measures failed. So I tried solution "B": Anhydrous isopropyl alcohol. I turned off the computer and unplugged it, then simply poured a couple of capfulls of the stuff onto the mainboard where the keyboard and mouse are connected, and let it dry completely. [This is important only of you don't want the computer to explode in a burst of flame. If you don't mind explosion and fire, go ahead and try it when the computer is running.] I had to do it twice, but the computer has functioned flawlessly ever since.

Note the word "anhydrous" above. If you use 70% or even 90% alcohol, you are pouring water into your computer, which is a blunder. Water will destroy it.

I have used anhydrous isopropyl alcohol for many other computer problems and it usually works, but not always. After all, mainboards DO occasionally burn out.

There are other "contact degreasers" out there in spray cans which work as well, but beware: some of these destroy plastics and will turn your computer into a doorstop or boat anchor. Only use those contact cleaners that say "approved for electronic circuits" or something similar.

David F Mayer