Apple’s own advice for keeping data secure during repair:
For Macs: Keeping your confidential data secure during hardware repair
When your hard drive is replaced, the previous hard drive is returned
to Apple and refurbished. As part of the refurbishment process, Apple
erases and reformats all hard drives to help address any concerns
about data security or identity theft.
You might send your computer
for repair when the hard disk is still working—either the drive works
intermittently or your hard drive isn't the issue requiring repair. If
you are concerned about data security and your hard disk is still
functioning, you should back up your important data and use the secure
erase functions in Disk Utility (described below) to reformat your
drive before sending in your computer for service.
Secure erase functions in Disk Utility
Your erase options depend on which version of OS X you have on your computer.
- Mac OS X v10.4 and later includes additional secure erase options in Disk Utility. Note: With OS X Lion v10.7 or later and an SSD drive, Secure Erase and Erasing Free Space are not available in Disk Utility. These options are not needed for SSD because a standard erase makes it difficult to recover data from an SSD. For more security, consider turning on FileVault encryption when you start using an SSD. FileVault, available in Mac OS X v10.3 and later, prevents others from easily accessing any information contained within your Home folder, even if the drive unexpectedly stops working or is serviced.
- Mac OS X v10.3.x and earlier include a
Zero all Data function in Disk Utility that you can use to completely
erase the drive.
Always remember to make a backup of your important
data before using any erase or encryption options, as any rewriting of
data includes a risk of data loss.
For iOS devices: Get your iPhone, iPad, or iPod touch ready for
service
Before you bring in your device
Follow these steps before you take your device to an Apple Store,
Apple Authorized Service Provider, or carrier. If your device won't
turn on or respond, finish as many steps as possible:
- Back up your iOS device.
- Have your Apple ID password ready. For some repairs, you'll need your Apple ID password to erase your device and turn off Find My
iPhone.*
- Bring your sales receipt (if possible), in case your service requires proof of purchase.
- Bring your device and any accessories that you need help with.
- Bring a form of personal identification, like a driver’s license, passport, or other government-issued ID.
- If you haven't already, call to check whether you need an appointment before you go to a service location. For example, schedule
a Genius Bar reservation before you go to an Apple Store.
Before you send your device
Follow these steps before you send your device in for repair or
replacement. If it won't turn on or respond, finish as many steps as
possible:
- If you need to send in an iPhone that's paired with an Apple Watch, unpair your devices. When you unpair, your iPhone will create a new
backup of your Apple Watch. You can use the backup to restore your
Apple Watch when your iPhone returns from service.
- Back up your iOS device.
- Go to Settings > Messages and turn off iMessage.
- Erase your device. Go to Settings > General > Reset > Erase All Content and Settings. If asked, enter your passcode and Apple ID
password. If you can't erase your device because it won't power on or
isn't responding, you can erase it from iCloud.com. Learn how.
- Make sure that Activation Lock is disabled.
- Remove any SIM card, case, or screen protector from your device and keep your cable and charger.