Moving to a new Mac? Before taking these steps, you can use Migration Assistant to move your files from the old Mac to your new Mac.
Create a backup
If your hard drive doesn't appear on the desktop, go to the Finder (you can select it in your dock or just click on your desktop) and select Finder Preferences (Command-Comma). Make sure the Hard Disks box is checked and it should show on your desktop. This is true as of OS X Lion (10.7) and subsequent OS X and macOS releases. Recovering data from a Mac hard drive to a PC is never an easy thing to do due to the incompatibility of the file system between Mac and PC. However, it's not without any solutions. If the file system of your Mac is the HFS+, congratulations, you can save your time by getting back your data directly without formatting. There are many options you can choose between, such as hard drive, USB flash drive and many others. Usually, when you plug the external device into your Mac, it appears as an icon on the desktop or can be found on the sidebar in Finder. However, sometimes you can't find external drive on Mac, and there are several reasons for that. Warning: If you have a solid-state hard drive, such as those included in the MacBook Pro with Retina Display, Macbook Air, or Winter 2012 iMac, do not attempt to defragment your hard drive. Defragmentation on solid-state hard drives can cause severe damage to the drive.
Make sure that you have a current backup of your important files. Learn how to back up your Mac.
Sign out of iTunes in macOS Mojave or earlier
If you're using macOS Mojave or earlier, open iTunes. From the menu bar at the top of the screen or iTunes window, choose Account > Authorizations > Deauthorize This Computer. Then enter your Apple ID and password and click Deauthorize.
Learn more about deauthorizing computers used with your iTunes account.
Sign out of iCloud
If you're using macOS Catalina or later, choose Apple menu > System Preferences, then click Apple ID. Pictures from android to mac. Select Overview in the sidebar, then click Sign Out.
If you're using macOS Mojave or earlier, choose Apple menu > System Preferences, click iCloud, then click Sign Out.
You will be asked whether to keep a copy of your iCloud data on this Mac. You can click Keep a Copy, because you're erasing your Mac later. Your iCloud data remains in iCloud and on any other devices that are signed in to iCloud with your Apple ID.
Apple External Hard Drive
Sign out of iMessage
If you're using OS X Mountain Lion or later, open the Messages app, then choose Messages > Preferences from the menu bar. Click iMessage, then click Sign Out.
Reset NVRAM
Shut down your Mac, then turn it on and immediately press and hold these four keys together: Option, Command, P, and R. Release the keys after about 20 seconds. This clears user settings from memory and restores certain security features that might have been altered.
Learn more about resetting NVRAM or PRAM.
Optional: Unpair Bluetooth devices that you're keeping
Apple Hard Drives
If your Mac is paired with a Bluetooth keyboard, mouse, trackpad, or other Bluetooth device that you plan to keep, you can unpair it. This optional step prevents accidental input when the Mac and device have separate owners but remain in Bluetooth range of each other.
If you're unpairing Bluetooth input devices from a desktop computer such as an iMac, Mac mini, or Mac Pro, you must plug in a USB keyboard and mouse to complete the remaining steps in this article.
If you're using OS X Mountain Lion or later, open the Messages app, then choose Messages > Preferences from the menu bar. Click iMessage, then click Sign Out.
Reset NVRAM
Shut down your Mac, then turn it on and immediately press and hold these four keys together: Option, Command, P, and R. Release the keys after about 20 seconds. This clears user settings from memory and restores certain security features that might have been altered.
Learn more about resetting NVRAM or PRAM.
Optional: Unpair Bluetooth devices that you're keeping
Apple Hard Drives
If your Mac is paired with a Bluetooth keyboard, mouse, trackpad, or other Bluetooth device that you plan to keep, you can unpair it. This optional step prevents accidental input when the Mac and device have separate owners but remain in Bluetooth range of each other.
If you're unpairing Bluetooth input devices from a desktop computer such as an iMac, Mac mini, or Mac Pro, you must plug in a USB keyboard and mouse to complete the remaining steps in this article.
Best Portable External Hard Drive For Mac
To unpair a Bluetooth device, choose Apple menu > System Preferences, then click Bluetooth. Move your pointer over the device that you want to unpair, then click the remove (x) button next to the device name.
Erase your hard drive and reinstall macOS
The best way to restore your Mac to factory settings is to erase your hard drive and reinstall macOS.
After macOS installation is complete, the Mac restarts to a setup assistant that asks you to choose a country or region. To leave the Mac in an out-of-box state, don't continue setup. Instead, press Command-Q to shut down the Mac. When the new owner turns on the Mac, the setup assistant guides them through the setup process.
No matter the model or condition, we can turn your device into something good for you and good for the planet: Learn how to trade in or recycle your Mac with Apple Trade In.
