Difficulty
Easy
Steps
6
Time Required
1 - 3 hours
Sections
1
- How to Install macOS High Sierra
- 6 steps
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Introduction
If you have recently upgraded or replaced the hard drive for your MacBook or iMac, you will need to reinstall macOS onto it. This guide will show you how to install macOS High Sierra onto a blank hard drive by using a bootable flash drive.
Before you begin, you will need to create a bootable flash drive. This requires having access to a Mac currently running High Sierra, in order to download the 7.7 GB High Sierra file in the App Store. You will also need an empty flash drive that can fit 5.4 GB.
Follow this guide to create a bootable macOS High Sierra flash drive before proceeding with the guide.
What you need
Step 1
How to Install macOS High Sierra
- With the device powered off, disconnect any external hard drives and flash drives.
- Plug in your macOS High Sierra bootable flash drive.
- Hold down the [option] or [alt] (⌥) key on the keyboard and power on the device.
- When you see the boot selection screen as shown, release the [option] key.
- Use either the keyboard’s arrow keys or the mouse to select “Install MacOS High Sierra.” Press [enter] or click your selection with the mouse.
With the device powered off, disconnect any external hard drives and flash drives.
Plug in your macOS High Sierra bootable flash drive.
Hold down the [option] or [alt] (⌥) key on the keyboard and power on the device.
When you see the boot selection screen as shown, release the [option] key.
Use either the keyboard’s arrow keys or the mouse to select “Install MacOS High Sierra.” Press [enter] or click your selection with the mouse.
1024
Step 2
- Your Mac will begin copying the installation files from the flash drive. This may take up to 30 minutes.
- Depending on the speed of your flash drive, it may look like progress has frozen, but it should resume if you continue to wait.
- When prompted, select your language and press [enter], or click the arrow button.
Your Mac will begin copying the installation files from the flash drive. This may take up to 30 minutes.
Depending on the speed of your flash drive, it may look like progress has frozen, but it should resume if you continue to wait.
When prompted, select your language and press [enter], or click the arrow button.
Step 3
- If you don’t need to pre-configure your hard drive, skip to step 5. If you’re not sure or if the drive is used, it’s a good idea to pre-configure your hard drive.
- Select “Disk Utility” from the menu and press [enter] or click the continue button.
If you don’t need to pre-configure your hard drive, skip to step 5. If you’re not sure or if the drive is used, it’s a good idea to pre-configure your hard drive.
Select “Disk Utility” from the menu and press [enter] or click the continue button.
Step 4
- Select your hard drive from the left column in Disk Utility.
- It is most likely the uninitialized drive.
- If you have multiple hard drives, make sure you select the correct one as the next step will wipe the selected drive clean.
- Click the “Erase” button at the top of the window.
- Choose a name for your drive (you can rename it later). Leave the scheme as GUID Partition Map.
- If you are installing an SSD, choose the APFS format. If you are installing a mechanical drive or if your device doesn’t officially support the newer OS, leave the format as Mac OS Extended (journaled)
- Click “Erase.” When the process completes, click “Done.”
- Exit the Disk Utility by clicking on the red X button on the top left corner of the window.
Select your hard drive from the left column in Disk Utility.
It is most likely the uninitialized drive.
If you have multiple hard drives, make sure you select the correct one as the next step will wipe the selected drive clean.
Click the “Erase” button at the top of the window.
Choose a name for your drive (you can rename it later). Leave the scheme as GUID Partition Map.
If you are installing an SSD, choose the APFS format. If you are installing a mechanical drive or if your device doesn’t officially support the newer OS, leave the format as Mac OS Extended (journaled)
Click “Erase.” When the process completes, click “Done.”
Exit the Disk Utility by clicking on the red X button on the top left corner of the window.
Step 5
- Select “Reinstall macOS” from the menu and press [enter] or click “Continue.”
Select “Reinstall macOS” from the menu and press [enter] or click “Continue.”
Step 6
- Read through the license agreement.
- Click “Agree” to accept the license agreement.
- Your Mac will now install macOS High Sierra. Be patient and wait for it to complete.
- Once the install is complete, the device will restart itself.
Read through the license agreement.
Click “Agree” to accept the license agreement.
Your Mac will now install macOS High Sierra. Be patient and wait for it to complete.
Once the install is complete, the device will restart itself.
High Sierra should now be freshly installed! Enjoy!
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Arthur Shi
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Iztok - Apr 22, 2012
Reply
I replace Toshiba MK1231Gal dard disk based on instruction on yutube http://www.youtube.com/watch?feature=pla…!
the problem is that when I try to install osx, I cant format the disk
I got notice input, output error, when try to make a partition or try anything with disk utility
I own MacBook air 1237
jay zee - Oct 29, 2016
yes, me too…did you get it fix? please share how.
littleduckltd - Dec 29, 2018
Use disk utilities from the Mac OS installer to format the new drive in a Mac format. Then install the Mac OS. New drive won’t show up in the installer until it’s Mac format.
Ben Capehart - Aug 10, 2022
DDD in this case
dard disk