Apple PowerBook (5300 Series) - Manual (Page 118)

This chapter provides a step-by-step approach to diagnosing and solving
problems involving system software and hard disks. Try the steps listed in
each section in the order they are given until your problems are fixed.
Checking your system software extensions
System software extensions are files that add features to your system software.
Some extensions are incompatible with one another or with certain programs.
To check whether an extension is causing problems, follow these steps:
1 Start up the Macintosh PowerBook while holding down the Shift key. Keep it held down
until you see the message “Extensions off” in the Welcome to Macintosh box.
This procedure turns off extensions.
If this procedure solves your problem, then continue with this section. If not,
then turn to the next section, “Testing Your Hard Disk.”
2 Restart the computer while holding down the keys Command ( x ), Option, P, and R until
you hear the startup sound repeat itself three times. Then release the keys.
This procedure resets the parameter RAM. For more information, see “The
Computer Makes an Unusual Sound at Startup” in the section “Problems
Starting Up the Computer” in Chapter 7.
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8
Diagnostic Techniques
Consult this chapter before you
call the Apple Assistance Center
to solve problems with system
software and your hard disk.