macOS Recovery makes it easy to reinstall the Mac operating system, even if you need to erase your startup disk first. All you need is a connection to the Internet. If a wireless network is available, you can choose it from the Wi-Fi menu , which is also available in macOS Recovery.
1. Start up from macOS Recovery
To start up from macOS Recovery, turn on your Mac and immediately press and hold one of the following sets of keys on your keyboard. Release the keys when you see an Apple logo, spinning globe, or other startup screen.
Command (⌘)-R
We reformat a hard drive if we are switching from one platform to another (Windows to Mac and vice verse) Back to the main topic, below is a step by step instruction on how to Format/Reformat a hard drive for Mac OS. Warning: FORMATTING and REFORMATTING A DRIVE ERASES EVERYTHING. Proceed with caution. Do backup your files first. Mac OS Extended (Journaled/HFS+): If you didn't update your Mac OS to High Sierra, the default file system on your Mac shoule be Mac OS Extended. Mac OS Extended (encrypted) would be an ideal option if you probably carry your laptop or external drive here and there. You can encrypt it so that no one can access the contents on your drive. Reformatting Required for Mac OS Compatibility. This article explains reformatting is required for macOS compatibility. How To Backup Files Using WD Backup. This answer explains how to backup files using WD Backup. External USB Storage Online User Guide and Solutions.
Reinstall the latest macOS that was installed on your Mac (recommended).
Option-⌘-R
Mts files importing with no audio mac adobe premiere cc. Upgrade to the latest macOS that is compatible with your Mac.
Shift-Option-⌘-R
Reinstall the macOS that came with your Mac, or the closest version still available.
You might be prompted to enter a password, such as a firmware password or the password of a user who is an administrator of this Mac. Enter the requested password to continue.
When you see the utilities window, you have started up from macOS Recovery.
2. Decide whether to erase (format) your disk
You probably don't need to erase, unless you're selling, trading in, or giving away your Mac, or you have an issue that requires you to erase. If you need to erase before installing macOS, select Disk Utility from the Utilities window, then click Continue. Learn more about when and how to erase.
3. Install macOS
When you're ready to reinstall macOS, choose Reinstall macOS from the Utilities window. Then click Continue and follow the onscreen instructions. You will be asked to choose a disk on which to install.
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 macOS Recovery exceptions.
If the installer offers you the choice between installing on Macintosh HD or Macintosh HD - Data, choose Macintosh HD.
Please allow installation to complete without putting your Mac to sleep or closing its lid. During installation, your Mac might restart and show a progress bar several times, and the screen might be empty for minutes at a time.
If your Mac restarts to a setup assistant, but you're selling, trading in, or giving away your Mac, press Command-Q to quit the assistant without completing setup. Then click Shut Down. Butler 422 homes. When the new owner starts up the Mac, they can use their own information to complete setup.
macOS Recovery exceptions
The version of macOS offered by macOS Recovery might vary in some cases:
If macOS Sierra 10.12.4 or later has never been installed on this Mac, Option-Command-R installs the macOS that came with your Mac, or the closest version still available. And Shift-Option-Command-R isn't available.
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. You can upgrade to a later version afterward.
If your Mac has the Apple T2 Security Chip and you never installed a macOS update, Option-Command-R installs the latest macOS that was installed on your Mac.
If you just had your Mac logic board replaced during a repair, macOS Recovery might offer only the latest macOS that is compatible with your Mac.
If you can't get macOS Recovery to offer the installer you want, you might be able to use one of the other ways to install macOS.
Other ways to install macOS
You can also install macOS from the App Store or Software Update preferences. If you can't install macOS Catalina, you might be able to install an earlier macOS, such as macOS Mojave, High Sierra, Sierra, El Capitan, or Yosemite.
Or create a bootable installer disk, then use that disk to install macOS on your Mac or another Mac.
WARNING: Formatting will erase all data on the device. Back up all your data before proceeding.
Instructions below are for 10.11.x (El Capitan) and 10.12.x (Sierra)
1. Double-click on Macintosh HD - or in the Finder menu clickFile > New Finder Window 2. Click the Applications folder - if using a Finder Window Applicationswill be in the left side menu. 3. Click the Utilities folder. 4. Double-click Disk Utility. 5. On the left side of the window are the drives connected to the computer. Select the capacity of the drive respective to the one containing the device you wish to format then click the Erase tab. Example: If the drive is called 'NO NAME', directly above that, you should see the drive capacity of 'XXXX'. Movist 2 1 10. Select this capacity. 6. Verify Volume Format is set to MS-DOS file system or exFAT, Scheme is set to “Master Boot Record” (Do NOT select GUID Partition Map) then click Erase.
Instructions below are for 10.13.x (High Sierra)
1. Open Disk Utility. Please See Answer 20985: How to access Disk Utility macOS 2. In the top menu bar, go to View, and choose Show All Devices
3. Select the upper level of the drive you would like to format and click the Erase button
4. Choose how you would like to format the drive
Enter a Name for your drive
Choose exFAT or MS-DOS (FAT) for the format
Choose Master Boot Record for the Scheme
Click Erase
5. When finished, the drive will be formatted and repartitioned successfully. Click the Done button
NOTE: exFAT is used on SDXC card (64GB and higher).
NOTE: exFAT can be used on flash drives or memory cards to transfer files larger than 4GB.
NOTE: MacOS 10.6.2 or higher is required for exFAT file system. Some older operating systems must have a patch installed before they can use the exFAT file system.
NOTE: If the above steps do NOT resolve the problem or if the lock switch is missing or broken, please back up your data and request a replacement using our online web form.
Mac Os Reformat External Drive
Related Articles: Operating systems that support exFAT Deleting files on a memory card using a Mac Deleting files on a Cruzer USB flash drive using a Mac