This document discusses the Archive and Install feature of the Mac OS X Installer. To learn more about this feature in Mac OS X 10.4 or later, see this document.Tip: Before reinstalling the Mac OS in an attempt to resolve an issue, you should make sure that other, simpler issue isolation steps have been tried. You should also make a back up of important files before any Mac OS X installation.About Archive and InstallAvailable 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.

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