Updating your Mac is essential if you want a long and a happy life for your estimator. Luckily, almost of those processes are automatized on Mac and you don't have to worry about installing updates. Nevertheless, if something goes wrong, yous'll go a "macOS could not be installed on your reckoner" fault message, and that'due south something that you should worry about.

This error can be caused by a few different issues. The good news is, they're all pretty easy to gear up yourself. Learn what could be causing the "macOS couldn't be installed on your reckoner" mistake and how to troubleshoot this issue on your Mac.

Why the macOS Couldn't Be Installed Error Appears

There are quite a few dissimilar reasons why a macOS installation might fail. Some of the most common reasons why you've been getting this error include:

  • Not having plenty complimentary space on your Mac
  • Issues with your startup disk
  • The macOS installer file's corrupted

The mistake message that pops up ordinarily comes with a message underneath it that gives you lot an explanation of what went wrong. The bulletin might say "the path/System/Installation/Packages/OSInstall.mpkg appears to exist missing or damaged", "an error occurred while verifying firmware", "unable to unmount book for repair", or something unlike. While these messages don't offer too much details on what the trouble is, they give you lot an idea of what stages of the installation process couldn't be completed.

No matter what acquired the error bulletin to appear on your Mac, you can fix it by following the troubleshooting steps described beneath.

How to Prepare Your Mac for Troubleshooting

Before you begin troubleshooting the macOS installation error, you might want to protect your data and make sure you don't lose whatsoever important data in the process.

Information technology's best if you make it a addiction to back up your Mac earlier installing whatsoever major updates. Major macOS updates affect the files in your operating system. Should something go wrong, you'll need to erase your Mac in lodge to fix it, meaning y'all'll lose any files that aren't a part of your near recent fill-in.

Y'all can backup your Mac using Disk Utility or Time Automobile earlier updating your calculator. It'll proceed your data rubber and give you an opportunity to restore the important files from the date of your option in case something goes wrong and you have to erase your entire Mac.

How to Troubleshoot the Error: macOS Couldn't Be Installed on Your Computer

After you lot've backed upwardly your Mac, you can go along to troubleshoot the error and complete installing the macOS update. Equally there are enough of things that could be causing problems with your macOS update, whatsoever of the following methods might fix the trouble. We recommend that you lot give all of them a try, starting with the easiest and quickest ones from the superlative of the list.

Restart Your Mac and Retry Installation

Restarting your Mac and trying to do the thing that but failed might seem giddy, but sometimes all your Mac needs to sort whatever problems out is a restart.

To restart your computer, open the Apple menu in the upper-left corner of your screen and select Restart. If your Mac's frozen, yous tin can use the Ability button to force a shutdown and and then restart the estimator. After that, effort the installation again and encounter if information technology works.

If information technology doesn't work and your Mac'south stuck on a loop launching macOS installer upon restart, you might need to boot up in Safe Fashion earlier you tin can move onto the side by side footstep. To do that, press and agree the Power push until your Mac shuts down. Then press and hold Shift when restarting your figurer. When you boot up your Mac in Safe Way, the installer won't launch upon startup.

Check Your Date & Time Settings

Cheque the Date & Time settings on your Mac. If the date or time is wrong (i.e. doesn't match the reality), this could be causing the bug when connecting with Apple tree's servers and lead to an fault installing the macOS update.

To set up your Date & Time settings, follow the path Apple bill of fare > System Preferences > Date & Time. Select the lock icon and enter your countersign to make changes. Then ready the engagement and time manually or select Set date and time automatically. After yous're finished, run the installation once more and see if it works.

Free Upwards Space on Your Mac

Fifty-fifty though most macOS installers accept up around 5GB of storage, your Mac really needs to have about 20GB of free space to complete an installation. It's because the macOS installer needs extra storage to work and unpack files and folders.

Check how much gratuitous space your computer has before trying to install the update. Follow the path Apple carte > Almost This Mac > Storage. The gratis space is marked Available on the right side of the bar. Select Manage to come across which files are using the well-nigh space in detail.

If yous find that there isn't enough space to complete the macOS installation, you tin can use diverse methods to free up storage on your computer.

Download a New macOS Installer File

Since the installation procedure was interrupted, the macOS installer might have go corrupt. The next footstep is to move the installer file to Trash and replace it with a new one.

You can download a new re-create of macOS installer directly from Apple tree'southward back up page, or using the App Shop or System Preferences on your computer. Once you lot've downloaded the new macOS installer, endeavor to launch the installation procedure again.

Reset the NVRAM

The NVRAM stores diverse settings such as the time, screen brightness, monitor resolution, and the startup disk on your Mac. When these settings change and errors occur, this may cause problems with your macOS installation process.

The solution here is to reset your NVRAM and attempt the installation again. To do that, restart your Mac and agree Option + Cmd + P + R while it starts (near 20 seconds). Then try installing the macOS update again.

Run Disk Utility's First Assist

One of the possible causes for the fault in the macOS installation process are disk permission or fragmentation errors on your startup deejay. They're easy to fix using the pre-installed app on your Mac chosen Deejay Utility.

To do that, follow the path Applications > Utilities > Deejay Utility. Then select your Mac's startup disk from the sidebar (ex. Macintosh HD) and select Outset Help. Disk Utility will scan your startup deejay for errors and repair them. This set up is specially useful if you're getting the "unable to mountain volume" error when trying to install the macOS update. After information technology'south done, endeavor to install the macOS update again.

Reinstall macOS on Your Mac

This one's probably the well-nigh time-consuming method, merely if y'all're still getting the same error during the macOS installation y'all might accept to reinstall the whole operating system on your Mac.

To reinstall macOS, you'll need to restart your Mac and boot up in Recovery Style by holding Option + Cmd + R while your computer starts. Later on virtually twenty seconds y'all'll see an Apple logo – you can now release the keys. From the macOS Utilities window, select Reinstall macOS to install the latest version of macOS on your computer. Make sure to let some fourth dimension for this, since your Mac will first need to download the new software and then install it.

Restore from a Fill-in

If zip else works, the final troubleshooting method is to erase your startup disk and reinstall macOS from scratch. After that's complete, y'all can restore all of your data from a backup. Unfortunately, y'all'll lose anything that's non included in your about recent backup.

What to Practise to Preclude Future macOS Errors

Getting an error message that interrupts your macOS installation is annoying. While y'all tin hands troubleshoot this, it however delays your computer's updating procedure and can be extremely fourth dimension-consuming.

There are plenty of diagnostic tools for Mac that y'all can utilise to find and resolve whatever future bug before they even become a problem. It'south much easier and quicker to prevent any errors from disrupting your computer's work in the commencement place.

Have y'all ever had to bargain with the error "macOS could not be installed on your computer"? Which troubleshooting technique worked for you lot? Share your feel with installing macOS updates in the comments section below.