OS X Recovery Disk Assistant lets you repair disks or reinstall OS X without the need for a physical disc. The tool allows you to create OS X Recovery on an external drive that has all of the same capabilities as the built-in OS X Recovery: reinstall Lion or Mountain Lion, repair the disk using Disk Utility, restore from a Time Machine backup, or browse the web with Safari. Flash for macbook pro download. Testing conducted by Apple in October 2020 on production 1.4GHz quad-core Intel Core i5-based 13-inch MacBook Pro systems with 8GB RAM, 256GB SSD, and prerelease macOS Big Sur. Systems tested with WPA2 Wi-Fi network connection while running on battery power, with display brightness set to 12 clicks from bottom or 75%.
Start up from macOS Recovery
Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps:
- Apple silicon: Turn on your Mac and continue to press and hold the power button until you see the startup options window, which includes a gear icon labeled Options. Select Options, then click Continue.
- Intel processor: Make sure that your Mac has a connection to the internet. Then turn on your Mac and immediately press and hold Command (⌘)-R until you see an Apple logo or other image.
If you're asked to select a user you know the password for, select the user, click Next, then enter their administrator password.
Reinstall macOS
Select Reinstall macOS from the utilities window in macOS Recovery, then click Continue and follow the installer's instructions.
Follow these guidelines during installation:
- Allow installation to complete without putting your Mac to sleep or closing its lid. Your Mac might restart and show a progress bar several times, and the screen might be empty for minutes at a time.
- If the installer asks to unlock your disk, enter the password you use to log in to your Mac.
- If the installer doesn't see your disk, or it says that it can't install on your computer or volume, you might need to erase your disk first.
- If the installer is for a different version of macOS than you expected, learn about other installation options, below.
- If the installer offers you the choice between installing on Macintosh HD or Macintosh HD - Data, choose Macintosh HD.
After installation is complete, your Mac might restart to a setup assistant. If you're selling, trading in, or giving away your Mac, press Command-Q to quit the assistant without completing setup. Then click Shut Down. When the new owner starts up the Mac, they can use their own information to complete setup.
Other macOS installation options
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By default, macOS Recovery installs the latest macOS that was previously installed on your Mac.* You can get other macOS versions using one of these methods:
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- On an Intel-based Mac, you can use Option-Command-R at startup to upgrade to the latest macOS that is compatible with your Mac. Exceptions:
- If macOS Sierra 10.12.4 or later was never previously installed, you will receive the macOS that came with your Mac, or the closest version still available.
- If your Mac has the Apple T2 Security Chip and you never installed a macOS update, you will receive the latest macOS that was installed on your Mac.
- On an Intel-based Mac that previously used macOS Sierra 10.12.4 or later, you can use Shift-Option-Command-R at startup to install the macOS that came with your Mac, or the closest version still available.
- Reinstall macOS from the App Store instead of using macOS Recovery. If you can't install the latest macOS, you might be able to install an earlier macOS.
- Create a bootable installer, then use it to install macOS on your Mac or another Mac.
* If you just had your Mac logic board replaced during a repair, macOS Recovery might offer only the latest macOS compatible with your Mac. If you erased your entire disk instead of just the startup volume on that disk, macOS Recovery might offer only the macOS that came with your Mac, or the closest version still available.
These key combinations apply only to Mac computers with an Intel processor.
To use any of these key combinations, press and hold the keys immediately after pressing the power button to turn on your Mac, or after your Mac begins to restart. Keep holding until the described behavior occurs.
- Command (⌘)-R: Start up from the built-in macOS Recovery system. Or use Option-Command-R or Shift-Option-Command-R to start up from macOS Recovery over the Internet. macOS Recovery installs different versions of macOS, depending on the key combination you use while starting up. If your Mac is using a firmware password, you're prompted to enter the password.
- Option (⌥) or Alt: Start up to Startup Manager, which allows you to choose other available startup disks or volumes. If your Mac is using a firmware password, you're prompted to enter the password.
- Option-Command-P-R:Reset NVRAM or PRAM. If your Mac is using a firmware password, it ignores this key combination or starts up from macOS Recovery.
- Shift (⇧): Start up in safe mode. Disabled when using a firmware password.
- D: Start up to the Apple Diagnostics utility. Or use Option-Dto start up to this utility over the Internet. Disabled when using a firmware password.
- N: Start up from a NetBoot server, if your Mac supports network startup volumes. To use the default boot image on the server, hold down Option-N instead. Disabled when using a firmware password.
- Command-S: Start up in single-user mode. Disabled in macOS Mojave or later, or when using a firmware password.
- T: Start up in target disk mode. Disabled when using a firmware password.
- Command-V: Start up in verbose mode. Disabled when using a firmware password.
- Eject (⏏) or F12 or mouse button or trackpad button: Eject removable media, such as an optical disc. Disabled when using a firmware password.
If a key combination doesn't work
If a key combination doesn't work at startup, one of these these solutions might help:
- Press and hold all keys in the combination together, not one at a time.
- Shut down your Mac. Then press the power button to turn on your Mac. Then press and hold the keys as your Mac starts up.
- Wait a few seconds before pressing the keys, to give your Mac more time to recognize the keyboard as it starts up. Some keyboards have a light that flashes briefly at startup, indicating that the keyboard is recognized and ready for use.
- If you're using a wireless keyboard, plug it into your Mac, if possible. Or use your built-in keyboard or a wired keyboard. If you're using a keyboard made for a PC, such as a keyboard with a Windows logo, try a keyboard made for Mac.
- If you're using Boot Camp to start up from Microsoft Windows, set Startup Disk preferences to start up from macOS instead. Then shut down or restart and try again.
Remember that some key combinations are disabled when your Mac is using a firmware password.
Learn more
- Learn what to do if your Mac doesn't turn on.
- Learn about Mac keyboard shortcuts that you can use after your Mac has started up.