B. Troubleshooting Whether it's a car engine or an operating system, anything with several thousand parts can develop the occasional technical hiccup. Mac OS X is far more resilient than its predecessors | B. Troubleshooting Whether it s a car engine or an operating system anything with several thousand parts can develop the occasional technical hiccup. Mac OS X is far more resilient than its predecessors but it s still a complex system with the potential for occasional glitches. It s safe to say that you ll have to do less troubleshooting in Mac OS X than in Mac OS 9 or Windows especially considering that most freaky little glitches go away if you just try these two steps one at a time Quit and restart the wayward program. Log out and log back in again. It s theother problems that ll drive you batty. . Minor Eccentric Behavior All kinds of glitches may befall you occasionally in Mac OS X. Your desktop picture doesn t change when you change it in System Preferences. A menulet doesn t open when you click it. A program won t open it just bounces in the Dock a couple of times and then stops. When a single program is acting up like this but quitting and restarting it does no good try the following steps in the following sequence. . First Resort Repair Permissions An amazing number of mysterious glitches arise because thepermissions of either that item or something in your System folder that is the complex mesh of interconnected Unix permissions described in Chapter 12 have become muddled. When something doesn t seem to be working right therefore open your Applications Utilities folder and open Disk Utility. Proceed as shown in Figure B-1. This is a really really great trick to know. Tip Many Mac mavens in fact believe in running this Repair Permissions routine after running any kind of installer just to nip nascent problems in the bud. That includes both installers of new programs and of Apple s own Mac OS X updates. Figure B-1. Click your hard drive s name in the left-side list click the First Aid tab click Repair Disk Permissions and then read an article while the Mac checks out your disk. If the program finds anything amiss you ll see messages like these. .