[Editor's note: This article is part of our series of articles on installing and upgrading to Mavericks.]
It used to be that when upgrading to a major new version of OS X, installing over an existing OS X installation--for example, installing 10.3 over 10.2--entailed some degree of risk, as existing applications, add-ons, and support files could conflict with the new OS. For this reason, many people used to perform a "clean install": wiping your hard drive (after backing it up, of course), installing the latest version of OS X, and then either using Setup/Migration Assistant to restore your applications and data, or manually reinstalling programs and copying over your data. (The Mac OS X 10.2 installer actually included an Archive And Install option, which preserved your original OS in a special folder while installing a completely new, fresh copy of 10.3. This feature was eliminated in the Snow Leopard OS X 10.6 installer.)
But a new download-and-install procedure debuted with Lion (OS X 10.7) and continued through Mountain Lion (OS X 10.8) and now Mavericks (OS X 10.9). Instead of a bootable installation DVD, you download the latest OS X installer to your Mac and install the new OS from the same drive. With the debut of Mavericks, as with Mountain Lion and Lion, many Mac users are asking two related questions: (1) Can you perform a clean install of Mavericks? and (2) Should you? Here's my take on each of these questions, which is essentially the same as with Mountain Lion last year.
Can you perform a clean install of Mavericks?
First, the technical question: Given that the OS X 10.9 installer doesn't include an official clean-install option, is it possible to perform such an installation? The simple answer is: Yes. As explained in my main article on installing Mavericks, the installer will let you install the new OS onto a blank drive. So if you first back up your existing Mountain Lion, Lion, or Snow Leopard (OS X 10.6) installation and all your files--I recommend creating a bootable clone using SuperDuper or Carbon Copy Cloner--you can then boot from a bootable installer drive, erase your Mac's normal startup drive, and install Mavericks on it. In fact, you can use the instructions in my article on how to install Mavericks over Leopard. Specifically, scroll down to the section called "The brute-force method" and perform Steps 1 through 7, substituting "Mountain Lion," "Lion," or "Snow Leopard" for "Leopard"--the result is a clean install.
Once you've done this, if you want to use Setup/Migration Assistant to restore data from your backup, proceed with Step 8. If you truly want a clean start, you'll instead need to manually copy your personal data from your backup to your new Mavericks installation, and then reinstall all of your software. (This is one situation in which the more apps you've purchased through the Mac App Store, the better--you just launch the Mac App Store app and click a few buttons to automatically reinstall everything you've purchased.)
Sign up for CIO Asia eNewsletters.