Chapter 23

Troubleshooting macOS


check Facing the ol’ “My Mac Won’t Boot” blues

check Dealing with the prohibitory sign

check Recovering from startup crashes

check Using High Sierra’s Optimized Storage

As a bleeding-edge Mac enthusiast and consultant with more than a quarter century of Mac experience, I’ve seen more than my share of Mac troubles. Over those years, I’ve developed an arsenal of mostly surefire tips and tricks that I believe can resolve more than 90 percent of Mac issues without a trip to the repair shop.

Alas, if your hardware is dead, then, sadly, neither you nor I can do anything about it because it is now a job for your friendly Mac repairman — and your fat checkbook or high-limit credit card. But if your hardware is okay, you have a fighting chance of using the suggestions in this chapter to get your machine up and running.

About Startup Disks and Booting

Although you usually see a stylish Apple logo when you turn on your computer, once in a blue moon, you may instead see a solid blue screen, a solid gray screen, a solid black screen, or something else entirely, as described ...

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