Consult this chapter before you call the Apple Assistance Center to solve problems with system software and your hard disk.
8 Diagnostic Techniques
This chapter provides a
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:
1Start 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.”
2Restart 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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