How to Fix the MacOS "Installation Failed" Error

Resolve this common MacOS installation error
5 minutes

"Installation failed" is a pretty common MacOS error that can occur during updates or upgrades. Unfortunately, it's pretty vague, leaving Mac users to wonder why the installation failed and how to fix it. Luckily, the "installation failed" error is incredibly easy to fix.

Unlike more complicated MacOS errors, one of the below steps are guaranteed to resolve the issue and get your installation up and running! In fact, you might not need all three steps to get fix the problem.

Now, let's get started! Follow the below steps to resolve the "installation failed" error and restart your MacOS installation.

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Click "Okay"

First, lets close the error window by clicking "Okay."

Double-Check Your Storage

Next, double-check your Mac's storage. Sometimes installations won't complete if there isn't enough space for your MacOS installation.

Your Mac hard drive also needs to have enough storage for day-to-day functionality. That means that if you have 14 GB of space on your "Macintosh HD," and the upgrade is 13.5 GB, that isn't enough space to upgrade your Mac and maintain its functionality. Ideally, you want to have no less than 5 GB of free space on your Mac at all times, but the ideal amount of free space is roughly 10 percent of your storage capacity.

Check your Mac's storage:

  1. Click the Apple Logo
  2. Select "About This Mac"
  3. Click "Storage"
  4. Calculate the amount of space your hard drive has versus the size of the installation

If your Mac has plenty of storage, move on to the next step!

Quit Any Open Apps

Ideally, you shouldn't have any apps open when you start a MacOS installation, but sometimes an app or two might be open and interrupting other processes. If you have any apps open, follow the steps below to close them! If you don't have any open apps, skip to the next step.

Close open apps:

  1. Right-click the open app in your dock. If you have a trackpad, a two-finger click is the same as a right-click.
  2. Then, click "Quit."

Repeat these steps for any open apps. You can always tell apps are open if they have a little dot below them in the dock.

Restart Your Mac

Lastly, restart your Mac. To restart your Mac, try the steps below:

Restart your Mac:

  1. Click the Apple Logo
  2. Select "Restart"

After restarting your Mac you can easily restart your MacOS installation!

Upgrade your Mac for Apple's latest software!
2 hours

Mac users are often intimidated by large upgrades, scared that they might lose data or end up dealing with installation errors that take up more time and energy than they anticipated, but the truth about upgrading is that it's actually relatively simple and easy. Even though upgrading your Mac can be intimidating, it's really about following the steps and waiting it out. Yes, it takes some time to upgrade your Mac, but you aren't obligated to sit and stare at your Mac's progress during that time. Actually, it is better to go through the steps and let your Mac upgrade seamlessly on its own as it's designed to. In fact, most upgrade errors that occur are actually caused by user error, when users get impatient with the speeds of the upgrade process or try to use it while the upgrade is downloading and before the steps are complete. Before upgrading, it is important to follow a few steps to simplify the process and avoid complications. Before upgrading: Set aside the time to upgrade- As I mentioned above, expect to be near your computer, even if you are just in the other room watching television or cooking dinner. Don't try to upgrade when you only have an hour until work, or will not be near your computer to finish the job! Check your storage- Your Mac needs to have plenty of space to accommodate the upgrade. Before beginning, check your Mac's storage to make sure it has enough space. Generally, an upgrade is around 13 GB, but your Mac also needs space to do all that it does in a day. So, avoid upgrading unless you have at least 20 GB of free space on your Mac. If you don't, consider clearing up some space. Consider your internet and location- What you are about to do requires a flat surface that will not absorb heat and that is close to your router. Don't upgrade your Mac on your bed. Find a flat surface that will allow the needed ventilation. Also, If you are far from your router, move closer. If there is a fridge, microwave, and other possible causes of Wi-Fi interference, change your Mac's location, so that you are getting the best internet speeds possible. If able, I recommend using an Ethernet cord so that you have the fastest speeds possible instead of Wi-Fi, though if you have good Wi-Fi and are within the range needed with your internet plan, don't worry about connecting directly to the router! Back up your Mac- Make sure all your data is safe and sound, and follow along with me as I upgrade from MacOS Big Sur to MacOS Monterey. While date loss when upgrading isn't incredibly common, it can and does happen. So, backup your data. Don't skip this step before following along! Plug in your Mac- If you don't plug in your Mac, you won't be able to upgrade (depending on which MacOS you currently have). The software will otherwise automatically prompt you to plug in your Mac. To make your life easier, you can also set up automatic updates. Now, let's get started! Follow along with me as I upgrade from MacOS Big Sur to MacOS Monterey! Note: Some of these steps may vary depending on the version of MacOS you have and are upgrading to.