How to Prepare a Mac Computer for Re-sell

When you are a Mac owner you can expect to own that iMac, Macbook, Mac Mini, etc. for a good long while. And when the time finally comes to sell your Mac there is a bonus: Macs have great resell value. They just hold their value better than most other computers. I found this to be true when I recently sold my Mac Mini G4.

The biggest question I had when preparing to sell my Mac was how to clean off all of my personal information and make sure it was irretrievable and also set up the computer with a fresh version of the Mac OS X operating system and have it ready to use for the new owner? After lots of searching and asking of fellow Mac users I found the answer. If you also are interested in selling your used Mac and you are wondering how to go about it, this down-to-brass-tacks, plain English tutorial will help you be on your way to doing just that.

Back up, Back up, Back up

You knew it was coming so do not be surprised that the first step is to back up any files that you want to keep. There are a few different ways to do this. The first way is to simply copy any files, pictures, mp3's or other items you want to retain to a portable flash drive or disk. This is the ideal way to back up your old information if you only have basic files you want to keep (i.e. you do not want to keep applications or back up your entire machine). Backing up to both a flash drive and a CD/DVD requires the same basic steps. For backing up to a flash drive just plug your drive into the Mac's USB port. An icon representing the drive will show up in the left sidebar of the Finder. Now simply browse through the Finder and drag and drop the folders and files you want onto the drive's icon. They will be copied and once you are done simply press the eject symbol next to the drive's icon and you are ready to move on.

For backing up to a CD/DVD, the steps are a little different but not much. Insert the disk. You may be prompted to tell the Mac if you want to use the disk in the Finder or iTunes. Select Finder. As with the flash drive, the CD/DVD icon will show up in the Finder's sidebar. Now drag and drop your folders and files to the disk and once you are finished click the yellow and black burn button next to the CD/DVD's icon (it looks a little like a radiation symbol). It will take a couple of minutes for the disk to burn. Once it has completed just click the eject button and you are done.

If you are wanting to back up your Mac's entire contents or if you a disk/flash drive provides insufficient storage, you can choose to back up to an external hard drive. Backing up to a hard drive requires more steps and is outside the scope of this article. Please your external hard drive's instructions or instructions on your particular Mac for more information on this type of storage.

Erase the Old Information

Thankfully you do not need any special software to complete the next step: erasing your old personal information. However you will need the disk that came with your Mac or Operating System. If your Mac is running the original OS that it came with, then use the dark grey colored restore disk that came with your computer. If you have purchased an upgrade to the OS (such as Snow Leopard) and you want to fresh install that version then you will need the disk for it.

Once you are absolutely sure you have backed up every file you want to retain, insert the Restore or OS disk into your Mac's optical (i.e. CD/DVD) drive. At this point we are going to use the Disk Utility tool that is included on the disk to blank out your hard drive and re-install Mac OS X anew.

Now with the disk in your Mac go up and click the Apple symbol at the upper-left corner of your desktop and click "Restart." The shut down process will begin. Once it has shut down it will automatically restart and you will hear the chime start-up sound. As soon as you hear this chime, press and hold the Option key. It is located two keys to the left and right of the Space bar. You will hear the disk being read in the in the optical drive.

Next you will see a screen which is probably new to you. It will be a plain blue screen showing two options: boot to the internal hard drive (on the left) or boot with the disk (on the right). Select the option on the right (boot with disk) and click the arrow button. Next you will be asked to choose a language. After doing so click the button to proceed. You will be met with the main screen of the installation disk. At this point go up to the Utilities menu and select Disk Utilities. You will be met with a screen with tabs along the top and your Mac's hard drive listed on the left side bar. Select "Macintosh HD" and then in the main window click the Erase tab. This is the tool which will erase your info. Click "Security Options" and you will be given the option to Zero Out Date, 7-Pass Erase and even a 35-Pass Erase. When information on a hard drive is erased, it still resides on the hard drive for a time. The computer simply tags that space as available but the data is still there until it is overwritten. Zeroing Out data will replace all information with a random string of 1's and 0's. Thus the original data is wiped out.

The Zero Out option will be sufficient for most people. But if your Mac was used for a business or contains other highly sensitive information then you may want to choose the 7-Pass Erase option to insure complete erasure of data. And for folks like attorneys, doctors, etc. who may have very sensitive or even confidential information, a 35-Pass Erase may be in order. Keep in mind that the higher the level of erasure, the longer the process will take (up to a few hours).

Choose an erase option and click the Erase button. Disk Utility will now begin wiping out your old data. This may take some time so leave the computer and let it do it's thing for at least an hour. It will notify you when the procedure is complete. Once complete click on "Disk Utility" in the toolbar at the top of the screen and Quit Disk Utility. You will be taken back to the main screen and you are ready to clean install the OS.

Clean Install the OS

Installing the OS at this point will be very straightforward. Follow the onscreen instructions (mostly clicking Install and continue) to begin the process. This will install the OS brand new and will be like a brand new Mac. You will also need to give the computer about an hour to install the OS.

Now part of the install process is to Register the computer and set up a user account. However since you are going to sell your Mac you do not want to set it up for yourself. So here is what I did.

When it comes time for the installer to ask you to register, simply press Command and Q at the same time. It will allow you to quit and then skip the registration process but still allow you to continue with the installation.

As the installation and set-up continues, you will be asked to enter a name and password for the user account. Rather than enter my name I simply entered the name Mac User and for the password I entered something generic such as he name of the type of computer it is (e.g. "Macbook", "iMac", "Mac Mini"). Upon selling the machine you can give this information to the new owner so that he can change the username and password to anything he wishes.

Continue on through the rest of the screens and your computer will boot into your fresh newly installed operating system. At this point you can eject the install disk. You are finished.

Finishing Touches

There are a few extra steps I took to insure full-satisfaction to the new owner of my Mac. These are not necessary.

Launch Disk Utility from within the OS (not from the disk) by going to the Applications folder and selected "Disk Utility." In Disk Utility select the Macintosh HD and in the main window click "Repair Disk Permissions." This will insure that there were no disk errors when installing the operating system. When it is finished, quit Disk Utility and click the Apple symbol in the toolbar and select "Software Update" to bring all software up to speed since it is probable that the OS straight from the disk is not current on all updates.

Finished!

Your computer is now clean and ready for a new user to take over use of it and you can be sure that all of your personal information is completely gone from the hard drive so there is no danger of unscrupulous people digging it up for dishonest purposes. So now go out, find a buyer, and get back some of the money you put into that Mac! Good luck!