Revised as of February 20, 2007

Simply using a computer taxes its system. Installing new programs, creating and deleting documents, starting and quitting software... these activities lead to slower performance and can cause ever-growing system problems.
So, you can either leave your computer off and use it as a paperweight, or do some regular maintenance and trouble-shooting to keep your computer system running smoothly. Just as you need to tune up your car occasionally, you need to tune up your computer sometimes!
Now, once upon a time, not that long ago, the information on this page was great for just about any computer. However, computers have changed drastically recently -- and not always for the better. Now, computer makers do their best to hide many computer functions so that, if you have a problem, you have to bring the computer into a shop -- or, even better from them, decide to chuck it and buy an entirely new one. This is bad for the environment, and bad for your pocketbook!
If you have an IBM clone computer (as opposed to an Apple Macintosh) that's running Windows 98 or older, or running an operating system other than Windows (and hurrah for you if you've gone that route), the information on this page should still help you. Otherwise, for IBM clone users with more recent versions of Windows, see Eleven Tips for Troubleshooting Software, a tip sheet by TechSoup.
If you have an Apple Macintosh running OS9 or anything pre-OSX, then the following should still help you as well to keep your computer system running smoothly.
Please note the disclaimer before attempting any of the following suggestions.
Basic Macintosh Maintenance and Problem Solving
For machines running OS6, OS7, OS8 or OS9
The Desktop file is an invisible file that keeps track of various activities on your Macintosh. Sometimes, it gets confused, and causes various problems (screen freezes, applications ending in errors, etc.).
To rebuild your desktop: while starting or restarting your computer, hold down the option and command keys (the command key is directly to the left of you space bar). Continue to hold down these keys until a message appears asking you if you want to rebuild your desktop (it appears after your extensions load, but before the Desktop appears). Let go of the option and command keys, then press "OK". Your Desktop will be rebuilt.
It's a good idea to do this at least once a month. There are several programs which will do a better job of cleaning out your desktop file. My favorite: a freeware product called TechTool. Look for it in software libraries on the Web.
Zap Your Parameter RAM
Also known as PRAM, this is where your Mac keeps track of your settings -- the date and time of day, mouse speed, startup driver preferences, etc. Like the Desktop file, sometimes it gets confused, and causes various problems (screen freezes, applications ending in errors, etc.).
For users of System 6, zap your PRAM by holding down the Command, Shift and Option buttons at the same time while opening the control panels from the Apple menu. The Mac will beep to tell you that the PRAM has been zapped successfully.
For users of System 7, hold down the Command, Option, P and R buttons at the same time while restarting your Macintosh. Keep holding this down until your Mac chimes five times, then let go to let your Macintosh boot normally.
It's a good idea to do this at least once a month. There are several programs which will do a better job of zapping your PRAM. My favorite: a freeware product called TechTool. Look for it in software libraries on the Web.
Investigate Extensions
Often, computer problems are caused by a disagreeable extension. Some extensions get corrupted; others are sometimes incompatible with other extensions.
If you are experiencing a problem with your computer, restart your computer with the extensions off (hold down the Shift key while hitting restart, then wait for the message "Extensions Off", and let go). Do as much as you can on your computer with the Extensions off (some applications won't run without the appropriate extensions); word processing software will usually run just fine without extensions. If your computer works, your problem could be in the Extensions.
If you have a program that lets you turn extensions off and on (such as Extension Manager), try turning various extensions off and on with each computer restart to see if you can find the Extension that causes your computer problems. If you don't have an extension Manager-type application, create a folder called "Disabled Extensions" and put them all in there. Then try adding various Extensions back into your Extension folder in your System folder with each computer startup, to see if you can find the Extension that causes your computer problems.
Remember that you have to restart your computer when you turn an Extension "off"; otherwise, it's not really off. Escaping
Press Command-Option-Escape to kill a process currently in the foreground. This is useful if your machine is taking way too long to finish something and is ignoring you, or if an application has crashed -- sometimes you can use this trick to regain control of your machine long enough to save your work from other applications and restart your Mac. (After you use this trick, you should generally restart as soon as possible, because memory may have been trashed.)
Basic IBM/Clone PC Maintenance and Problem Solving
Defrag
If you are on Windows 95 or above, you have an icon that will do this for you. Otherwise, Defrag your computer from DOS. If you are on a graphic operating system below Windows 95 (such as Windows 3.1), look for the icon that gets you to MS DOS. Click on this icon, and you will come to a blank screen with the C prompt:
c:/
This means you are in the "C" Drive. If this isn't what you are seeing (for instance, you are seeing "f:/" instead, then type in "c:/", and it will get you there). At the C prompt ("c:/"), type in:
>defrag /f
(note that there is a space in between "f" and the forward slash)
Hit Return. Your computer will take you through a process to Defrag your computer. If you haven't done this before, defragging may take 30 minutes or more.
When the Defrag is done, restart your computer or return to your other operating system (Windows, whatever) and work as normal.
Scandisk or Checkdisk
If you are on Windows 95 or above, you have an icon that will operate Scandisk for you. Otherwise, Scandisk or Checkdisk your computer from DOS. If you are on a graphic operating system below Windows 95 (such as Windows 3.1), look for the icon that gets you to MS DOS. Click on this icon, and you will come to a blank screen with the C prompt:
c:/
This means you are in the "C" Drive. If this isn't what you are seeing (for instance, you are seeing "f:/" instead, then type in "c:/", and it will get you there).
At the C prompt, type in:
>scandisk
Hit Return. If you get an error message that says Scandisk is not available, then type in:
>chkdsk
Your computer will take you through a process to Scandisk or Check Disk. If you haven't done this before, defragging may take 30 minutes or more.
When the Scandisk is done, restart your computer or return to your other operating system (Windows, whatever) and work as normal.
There are four general areas where printer problems can occur: the cabling/connections, the software of the documents you are trying to print, the system software/printer drivers, or the printer itself. If these suggestions don't solve your problem, they will at least help you narrow down the causes. If none of them work, be sure you note what you've tried to the support person you contact to help you.
Before You Call Technical Support
You may find a web site by someone that answers this problem for you.
Phoenix Macintosh Repair (pre-OSX systems)
Formerly at http://w3.ime.net/~deceiver/phoenixmacrepair.html
Type or copy and paste the URL into archive.org and you can view the materials
This archived site will help you to find out what is wrong with your Mac be it old or new. Empahsis is on older Macs. The manual is very extensive. The text alone prints out to over 80 pages.
File Extensions.org
File extensions are (usually) three letter codes at the end of computer file names that tell to operating system (Microsoft Windows, MAC OS X, Linux and Unix operating systems, etc.) what kind of file they are dealing with. For instance, a file with ".doc" is a Microsoft Word document (but can be opened by just about any word-processing program). File Extensions.org is a very large list of the file extensions, many with detailed explanations of each file type and the way they are used. "We have also tried to include a few of the common software programs that are associated with each of these file extension types." If you find a file in your computer with an unknown file extension, you can look up the information about desired file extension and its file associations.
A Circuit Rider's Guide to Troubleshotting PCs
Formerly at http://www.lincproject.org/toolkit/troubleshoot.htm
Type or copy and paste the URL into archive.org and you can view the materials
"My personal theory to computer problems is that there is a direct connection between the amount of stress a user is under and the number of times a computer will crash." Agreed!! This was produced by the Low Income Networking and Communications (LINC) Project, part of the National Center for Law and Economic Justice. Sadly, the project ended in August 2006.
TechSoup
This comprehensive web site provides detailed information about a variety of technology-related issues specifically for mission-based organizations. This includes resources and advice regarding databases. It provides some of the best information you can find regarding technology resources for mission-based organizations. However, it's entirely IBM/Clone-focused (there's no info specific for Macintosh), and they are focused on the very latest tech. Still, it's excellent -- I read it several times a month. TechSoup is a nonprofit based in San Francisco, California.
No representations of accuracy or suitability are made by the poster/distributor. This material is provided as is, with no expressed or implied warranty. USE AT YOUR OWN RISK. You are responsible for the health, welfare and actions of your computer and software! This document is the author's attempt to pass on information she wished she had had when she first started using a computer. The author assumes no responsibility for the use of information contained within this document.
I've found Macintosh to have great literature for its PCs. The same has not been true, however, for the IBM/Clone PCs. I've found the "For Dummies" books on these IBM-related operating systems to have been much more helpful than any literature that came with the computer product. The latest versions of these books are available at any computer store or any store that sells computer books; the older versions can be found in used book stores, eBay, and any web search.

Disclaimer: No guarantee of accuracy or suitability is made by the poster/distributor. This material is provided as is, with no expressed or implied warranty.
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