← Back to Archives

Preparing an old Mac for resale

system

I have an old PowerBook G4 that I want to sell, for whatever the market will bear, on eBay.

I put some thought into preparing it for sale. I wanted the hard disk wiped clean of any information I had. I also wanted the recipient to get a fresh, updated OS install but still have that new-user "Welcome to Mac!" video/music experience.

This is what I recommend:

  1. Boot from the Mac OS X install disk. Select the "Utilities" Menu and then "Disk Utility". We'll want to erase "Macintosh HD" securely. I suggest clicking on "Security Options..." and selecting a 7-pass erase. Let this sucker run, it takes about 3 hours per 100GB on your drive. Quit Disk Utility when it's done.

  2. Install Mac OS X. When it starts asking you questions, first, don't enter in a wifi password (you can do this when you get to a normal desktop). Then, enter in "test" wherever you can and make sure the user it sets up is simple like "test" with no password.

  3. When you get to a desktop, run Software Update and update everything.

  4. You might also want to run System Profiler (in the Apple menu, click "About this Mac..." and then "More Info"). You can save the system profiler information as an archive of your past Mac's stats. I just emailed it to myself.

  5. Next, shutdown the computer, power back up while holding Command-S, which will boot you into single-user mode (which will be white text on black background... you'll know you're "there" when a # sign is there as a prompt).

  6. Run the following commands, exactly as typed:

    mount -uw / rm -rf /Users/* cd /var/db rm .AppleSetupDone rm .com.apple.iokit.graphics rm -rf dhcpclient rm -rf samba shutdown -h now

    These commands do a few things: mounts your hard disk, removes all accounts in the /Users/ directory, removes the file that tells your Mac not to do the Apple Setup whizbang, removes a bunch of graphics, networking and printing information that should be reset when the Mac starts for the first time.

  7. Done! You can boot it back up now to see that it does go to the Mac "Welcome" celebratory introduction montage.

    BTW, if you've set your Mac up such that it has a "verbose boot" (where it shows you what's happening during boot), you will see this when you start it up again. You'll want to either boot back into single-user mode or add a line to the above that resets the boot arguments to be non-verbose. To do this, type

    nvram boot-args=

    in single user mode (setting verbose mode is accomplished by nvram boot-args="-v" in single-user mode or sudo nvram boot-args="-v" at the terminal).

Now your old Mac is wiped clean, with a fresh updated operating system.

You might want to take a few pictures of it, find all the stuff that goes with it and prepare an auction page on eBay. I'd also recommend being very careful on eBay these days as scams abound... I use PayPal with their insurance and I watch a few items like mine to set a decent (but low) starting price

(Note: I cobbled together the single-user commands in step 6 from the following posts at Mac Guru Lounge, TUAW and post 10 by DeltaMac on this MacOSXHints thread.)