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.

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 be able to download the 7.7 GB High Sierra file in the App Store. You will so 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.

Tools

Parts

No parts required.

  1. With the device powered off, disconnect any external hard drives and flash drives. Plug in your macOS High Sierra bootable flash drive.
    • 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.

  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.
    • 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.

  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.

  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.
    • 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 format as Mac OS Extended (journaled), and the scheme as GUID Partition Map.

    • 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.

  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."
    • Select "Reinstall macOS" from the menu and press [enter] or click "Continue."

  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.
    • 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.

Conclusion

High Sierra should now be freshly installed! Enjoy!

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Arthur Shi

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44 Comments

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

Iztok - 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

Iztok - Reply

yes, me too...did you get it fix? please share how.

jay zee -

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.

littleduckltd -

A small pointer for any who have the same issue. I put in an entirely new 2TB WD sata drive and then preformed a fresh install of snow leopard onto it. When I got to the section to choose which drive to install to there was no drive image.

I clicked at the top on disk utility, then picked the drive, clicked erase and erased the drive. THis actually formats it into a mac format. after this I closed disk utility and voila the drive was now visible and installation could commence.

Good luck

Sam - Reply

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