Mac OS X 10.5 Help
Reinstalling Mac OS X
Under some circumstances, you may need to reinstall Mac OS X. You can reinstall Mac OS X while keeping your files and user settings intact.
To reinstall Mac OS X:
Insert the Mac OS X Install Disc and double-click the Install Mac OS X icon.
Follow the onscreen instructions. In the pane where you select the destination disk, select your current Mac OS X disk (in most cases, it will be the only one available).
Click Options. If you want to save your existing files, users, and network settings, select “Archive and Install,” and then select “Preserve Users and Network Settings.” If you want to erase everything on your computer and reinstall Mac OS X, select “Erase and Install.” You can’t recover erased data.
Click Continue.
Click Customize to select which parts of Mac OS X you’d like to install, or click Install to perform a basic installation (recommended).
If you purchased a standalone version of Mac OS X, these installation instructions are in a booklet PDF file located on the Mac OS X Install Disc.
If you need to reinstall the version of Mac OS X that was on your computer when you purchased it, or if you need to restore all the software on your computer, including Apple, bundled third-party applications, and printer drivers, review the instructions in the manual that came with your computer.
If you need to reinstall Mac OS X and you’ve been using Time Machine for backup, you can easily restore your applications, files, and user settings from your Time Machine backup file after you’ve reinstalled Mac OS X.