When you want to retire, sell or give away a Mac, you should never just pass it on to someone else as-is.
There are many apps that only allow you to use your serial numbers a limited time, most notably from Adobe and Microsoft. You should deactivate the software so that you can reuse your serial numbers on a new Mac.
There's other data you should save and remove also. In his article "iCloud services can make decommissioning your Mac more complicated," our good friend David Morgenstern at The Apple Core on ZDNet alerts us to an update to an Apple support article that deals with just that issue.
The first critical issue, as noted on The Apple Core, is to not manually delete any of your data while signed into your iCloud account. Your iCloud account stores your files that sync with all of your devices and removing anything while signed in means your other devices will also have that information wiped.
The safe steps to take are:
- Open iTunes and deauthorize the Mac from your iTunes account.
- Next, Apple recommends you back up your data. The Mac Basics: Time Machine support article, covers how to backup your Mac. You can also use other backup software, such as Carbon Copy Cloner or SuperDuper!. Both programs are used religiously by TUAW staff members. No matter what you use, the point is to make sure you have a copy of all of the data on your computer, so that you experience no surprises when you add a new Macintosh into your hardware mix.
- Open iCloud from your System Preferences. Uncheck the Find My Mac preference (the last one in the list), and then click the sign out button on the left side of the iCloud preference window. Your system automatically removes all of your iCloud data at this point. If you've backed up your data though, you still have it all neatly stored away on your backup drive.
The balance of the information on Apple's support article covers reformatting your hard drive and how to return it to its original "out-of-the-box" state. This is especially useful for the recipient of your old and their new Mac.
I recently had a relatively new iMac go belly-up on me and can say that having a current backup is the only thing that saved me from weeks of frustration trying to resurrect files. For my iTunes account, I just had to deauthorize all my machines and reauthorize them one by one. If I had not activated my iCloud account, I would have lost all my contacts, calendars and years of carefully organized Safari bookmarks. In addition, I found that Microsoft's phone support and Adobe's chat support were most helpful in returning my lost activations for their software.
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