Various Tips Macintosh Help
Mac application crash or freezing
If an Mac application crashes or is unresponsive, but you can still move your mouse, press the command, option, and escape keys (hold down command, then hold down option, then hold down escape, then let go of the keys).
Mac OS 9
A box asking if you want to force the application to quit will open.
Click on Force quit.
If the application successfully quits, restart your Mac before doing anything else.
If the application does not quit, restart your Mac.
Mac OS X
A window will open listing the current applications that are open.
Click on the Application that is not responding.
Click on the Force Quit button.
Click the red button in the upper left corner to close the Force Quit window.
You do not have to restart the computer.
If your Mac freezes completely, you can press the command, control, and power key keys to restart your Mac. This will not work on an iMac, blue and white G3, or G4. On the original iMac's, you will need to use a paper clip to press the small Restart button (the one with a triangle) between the ethernet port and the modem port. The next generation of iMac's have a button you can press. On the blue and white G3s and older G4s, press the tiny Restart button (it has a triangle on it) on the front of the computer. For the newer iMac's, G4s and G5s, press and hold the power button for about 5 seconds to turn off the computer. Wait about 30 seconds, and then press the power button again to turn the Mac back on.
To eject a diskette or CD that will not eject, hold down the mouse button (and keep holding it down) then restart or turn on the Macintosh. Keep holding down the mouse button until the disk or CD is ejected. If this does not work, then try inserting a paper clip into the tiny round hole near the CD or diskette drive. (You may need to move the paper clip about before you can eject the CD or diskette.) Be careful not to damage your media or drive when using this method.
Rebuild the desktop once a month
The desktop file is an invisible file on your Macintosh that keeps track of all the documents and applications (as well as their icons) that are on your computer. Over time, this file may become damaged. It is usually a good idea to rebuild the desktop file once a month.
To rebuild the desktop file, hold down the command key (the one with the apple symbol) and the option key while your Macintosh is starting up. Keep holding down these two keys until you see a prompt asking you: "Are you sure you want to rebuild the desktop file on the disk 'hard disk name'?". Release the keys and click OK.
For a more detailed description of the desktop file and how to rebuild it, please read the Apple article
Run Disk First Aid once a month
Every Macintosh comes with a utility called Disk First Aid. Its icon looks like an ambulance (Mac OS 9). Disk First Aid can also be found on your Macintosh system software CD "Disk Tools" or "Utilities" folder.
To check your hard drive, launch the Disk First Aid application and select your hard drive. If you Disk First Aid reports errors, it is recommended that you repair them. To repair the errors you will need to start your Macintosh off of the original system CD and then run Disk First Aid 'repair'.
Consider purchase of a disk repair program
Commercial disk repair programs continue where Disk First Aid leaves off. It is a good idea to have both Disk First Aid and at least one disk repair program as part of your Macintosh software collection, since each can find and repair errors that the other can't. In fact, it may even be a good idea to own more than one disk repair program since in many cases if one can't fix the problem the other can.
Regularly checking your hard drive with a commercial disk repair program will also lessen the chances of something going wrong with your computer. Some Macintosh disk repair programs are:
Symantec's Norton Utilities
MicroMat's TechTool Pro
Norton Utilities includes Norton Disk Doctor. If you decide to use Norton Utilities as your disk repair program, please be aware that certain Macintosh computers require specific versions of Norton Utilities. If you use the wrong version you may corrupt your hard drive.