Mac OS X: The Missing Manual, Second Edition

The Clean Install

In Mac OS 9 and Windows, the clean install is considered an essential troubleshooting technique. It entails installing a second System Folder or WINDOWS/WINNT folder—a fresh one, uncontaminated by the detritus left behind by you and your software programs.

In general, though, you and your software can’t invade the Mac OS X System folder. The kind of gradual corruption that could occur in those older operating systems is theoretically impossible in Mac OS X, and therefore the need to perform a clean install is almost completely eliminated.

That’s the theory, anyway. In fact, somehow or other, things can go wrong with your Mac OS X installation. Maybe someone was fiddling around in Terminal and accidentally deleted or changed some important underlying files. Certain shareware programs can perform deep-seated changes like this, too.

The point is that eventually you may want to start over with a pristine, perfect copy of Mac OS X. And now, thanks to the new Clean Install option, you can—without having to erase the hard drive first, as you did in earlier Mac OS X versions.

Note

You can’t perform a clean install “upward” from an earlier version of Mac OS X—only from 10.2. In other words, if you have 10.1 and want a clean, perfect installation of 10.2, perform an Upgrade installation first, as described above. Then perform another installation, this one a clean one, as described here.

Start by following steps 1-4 that start in Section A.3.1. When you come to the Select a Destination ...