Apple Macintosh Performa 570 series - Manual (Page 65)

Check the startup disk and program you were using when the problem
occurred. Make sure that all programs, desk accessories, and system
extensions you’re using are compatible with the system software. Try starting
up the computer with the Utilities floppy disk or, if you have a built-in
CD-ROM drive, with the Macintosh Performa CD. (For instructions on how
to start up your computer from the CD-ROM disc, see “Starting Up From
a CD-ROM Disc” in the section “Repairing a Damaged Disk” later in this
chapter.) If your computer starts up normally, there may be an extension
conflict.
Sometimes incompatible system extensions or control panels can cause
system software problems. Restart while holding down the Shift key; this
temporarily turns off all system extensions. If your computer works
normally after you do this, remove all extensions from the Extensions
folder (inside the System Folder) and put them back into the Extensions
folder one at a time. Restart after you add each extension. This procedure
should identify any incompatible extensions.
You can also use the Extensions Manager control panel to turn off
individual extensions. For information on using this control panel to
manage system extensions, see the “Setting Options” topic of Macintosh
Guide, available in the Guide (h) menu.
If the problem recurs, you may need to reinstall system software. See
“Installing or Reinstalling System Software” later in this chapter for
instructions.
m The mouse is not connected properly.
Turn the computer off using the power switch, check that the mouse and
keyboard cables are connected properly, and then restart the computer.
m Signals from the mouse are not reaching the computer, either because the
mouse needs cleaning or because there is something wrong with the
mouse.
Clean the mouse according to the instructions in Appendix A of this book.
If you have another mouse or pointing device, try connecting and using it.
(Turn off the computer before connecting it.) If the new device works, there
is probably something wrong with the mouse you replaced.
If none of these procedures solves the problem, consult the service and
support information that came with your computer for instructions on how to
contact an Apple-authorized service provider or Apple for assistance.
57 Troubleshooting