Available in Mac OS X 10.2 and later, an Archive and Install installation automatically moves existing system files to a folder named Previous System, then installs Mac OS X again. (See tip 3.) You cannot start up your computer using a Previous System folder, nor can you "re-bless" the Previous System folder. (See tip 1.)
You can choose to preserve your user and network settings before installing. This option automatically moves existing users, Home directories, and network settings. This also skips the Setup Assistant after installation.
Note: Because the "Preserve user and network settings" option moves, not copies, existing users, Home directories, and network settings, from the Previous Systems folder to the newly installed System, these items will not exist in the Previous Systems folder after the Archive and Install is complete.
If Mac OS X is not already present, you cannot select Archive and Install. You must Install or Erase and Install instead.
How to use Archive and Install
Tip: Before starting the installation, you may wish to use Disk Utility to verify and repair the volume. See "Mac OS X 10.2: Directory Issue Verification or Repair Is Not Part of Installation".
1. Start up from your Mac OS X Install Disc 1 or Install DVD. If you have different versions of Mac OS X Installer discs (for example, if your computer came with version 10.3 and you later purchased and installed version 10.4), start from the disc that most closely matches the installed Mac OS X version. Usually, that's the latest (newer) version.
2. Select your language. The Welcome to the Mac OS X Installer window appears.
3. Click Continue. The Important Information window appears.
4. After reading or printing the information, click Continue. The Software License Agreement window appears.
5. After reading or printing the information, click Continue.
6. An agreement sheet appears. If you agree with the license agreement, click Agree. The Select a Destination window appears.
7. Click the volume that you wish to install to.
8. Click Options. The installation options sheet appears.
9. Select Archive and Install.
10. Select the volume which already has Mac OS X installed.
11. You should also select Preserve Users and Network Settings, to preserve network and Home directory settings. (See notes and Related documents below.)
12. Click OK.
13. Click Continue to begin the installation.
Tips and notes
1. The Archive and Install feature is not available in Mac OS X 10.2 Upgrade CDs. It is only available with standard retail CDs, and on installation CDs or DVDs that come with new computers.
2. Some third-party software items may not be preserved. If third-party software doesn't work after the Archive and Install is performed, reinstall it or contact the vendor.
3. The version of Mac OS X installed by this process is the same version included on your installation CD or DVD. If you have installed Mac OS X updates, they are not automatically re-installed by this process. For information about updating Mac OS X, see Mac OS X: How to Update Your Software.
4. Some applications may store items in the Shared folder, and these items may be missing after the Archive and Install. See "Mac OS X 10.2: Contents of Shared Folder Missing After Archive and Install".
5. Archive and Install does not affect your Mac OS 9 System Folder, if you have one, but you may need to reselect it in Classic preferences after performing the installatio