When Apple releases a new version of Mac OS X, you can download it from the Mac App Store and install it on your computer seamlessly.
However, a few Mac users have reported coming across installation problems with the error message “OS X could not be installed on your computer” popping up on the screen.
First, we’ll look at several reasons you could be getting the “OS X could not be installed on your computer” feedback. Next, we will show you the best fixes for the problem.
Causes of the “OS X Could Not Be Installed on Your Computer” Feedback
The most likely reason for this error message is insufficient disk space or incorrect time. Also, an installer file may be corrupt or something could be wrong with the startup disc.
Another potential hurdle for the update is when the permissions are not optimally set. In this case, the installation will abort while leaving an error message.
“OS X Could Not Be Installed on Your Computer”? Best Fixes
OS X updates and the reinstallation troubleshooting process should always begin with a full data backup.
You can make a Time Machine backup or a clone of the current operating system to a hard drive. If something goes wrong with the update, you can always restore your computer from the Time Machine backup or copy the data back to your Mac. Programs that help to create a clone are, for example, SuperDuper or Carbon Copy Cloner.
Fix 1: Fix space issues
The macOS installation wizard often aborts the installation if there is not enough hard drive space on the computer.
A new system such as macOS 11 Big Sur now requires at least 35.5 GB of hard drive space, sometimes significantly more if you switch from El Capitan.
For security reasons, you should only start the update when there is at least 50 GB of free hard disk space on the Mac. The maintenance updates in between can also be quite extensive.
If there isn’t enough free space, the Mac will throw up an error message and you’ll have to free up enough space before starting the procedure again.
However, in the newer systems, especially the Big Sur, this leads to an endless reboot mode because the installer apparently does not check whether there is enough free memory on the system.
You will come across the message “There was an error installing the update” and the installation will start again until the same error comes up again. The only solution, in this case, is to free up memory space.
Fix 2: Reinstall macOS via the internet
If you have backed up your data and you keep getting the error message, the easiest way to successfully reinstall macOS is via the Internet. To start the reinstallation, follow the process below:
- Hold down the Command (⌘) and R keys while restarting.
- The assistant will start. Then you have to download macOS from the Mac App Store and then reinstall it.
- However, the process can take a few hours, depending on the speed of your Internet connection and your Mac.
- Before reinstalling, you should run a hard drive repair from the recovery environment using Disk Utility. This often fixes bugs that affect OS updates.
Fix 3: Use combo update
If you fail to update the macOS, for example, because you couldn’t get to download via the App Store, you can download the corresponding combo update from the Apple support page. But Apple only offers this up to macOS 10.15 Catalina and no longer after Big Sur.
- To do this, search for the version of the update, for example, “macOS Catalina” and the term “Combo Update”.
- Open the link and download the installation file.
- If you install the update this way, the installation program with the combo updater should go through without any problems.
Fix 4: Correct the time
If the update installation fails, it is often due to an incorrect time.
- Go to the date and time settings in the system settings.
- Make sure the “Set date and time automatically” option is checked. By enabling this option, the Mac connects to the Internet and resets its time.
If the time cannot be set in the graphical user interface, you can also have the setting updated in the terminal. The time synchronization command line for this is:
sudo ntpdate -u time.apple.com
If you do not want to synchronize the time with the Internet, but set it manually, for example to 11/13/2020 at 12:30 p.m., use the command:
In this way, you can also repair faulty installations using the recovery program when booting the Mac. If the installation does not succeed here either, call up the terminal and set the time correctly. To start the recovery, hold down the Command (⌘) and R keys while restarting.
Fix 5: Repair partition with Disk Utility
If the OS X could not be installed on your computer, it could be because the partition cannot be adjusted while installing a new Mac version or during a major update.
- You can often fix such errors in Disk Utility. Call it up and click on “First Aid“.
- After that, start running the scan process and let it fix the hard drive. Then restart the installation of the update.
If that doesn’t work, start the recovery of macOS while booting the computer and then start the disk utility. To start the recovery, hold down the Command (⌘) and R keys while restarting.
Fix 6: Reset permission
As earlier mentioned, installation can be aborted due to missing user rights.
- In this case, boot the Mac in recovery mode. To start the recovery, hold down the Command (⌘) and R keys while restarting.
- After that, open a new terminal window and type “resetpassword”.
- Reset the password and have the permissions reset as well. Then restart the computer and reinstall the software.
Fix 7: Fix error for recovery system during installation
If you get a message like: “Install Failed: macOS could not be installed on your computer. OS X can’t be installed on the disk because a recovery system can’t be created”, this indicates that the partition size is too small for the recovery partition.
In this case, use the disk management program to check the partitioning of the hard disk on which you want to install or update macOS.
- To do this, use either the recovery system or Disk Utility of the currently installed version of macOS.
- Shrink the current partition a bit so the installer can use the free space itself. 128 MB is often sufficient here.
How do I force a Mac OS X to install?
To force a Mac OS X to install, start the Mac, by pressing Shift-Option and Alt-Command-R. When the Utilities screen pops up, choose the option to reinstall macOS. Continue by following the instructions. Select the startup disk. Click on install.
Why can’t OS X be installed on Macintosh HD?
The OS X will not install on Macintosh HD if you can’t create a recovery system.
How do I recover OSX?
You can reboot your Mac into Recovery mode by simply holding down the Command key and the R key.
How do I reinstall OSX High Sierra?
Always back up the computer before starting. Then reboot it while holding down both the Command and R keys after hearing the boot sound. The Mac will therefore boot into Recovery mode. Next, choose to reinstall macOS when you get to macOS Utilities.