macOS Big Sur Installation Failed? How to Solve?

Posted by Kaylee Wood | Last update: November 13, 2020 | 3 Mins Read

"an error occurred while installing this update" while upgrading Big Sur on MacBook Pro Early 2015. – asked by S Sayeed

Unable to download macOS Big Sur. – asked by alexcriq

I have errors during installation and the update to SUR is blocked. – aksed by JBCROSSUSA

If you are trying to update your macOS Catalina or Mojave Mac to macOS Big Sur but just fail, you are not alone to get the error notification. When macOS Big Sur is available to download, the most mentioned words are "Installation Failed. An error occurred while installing the selected update". I have to say, the bad comments flood. After ransacking the Apple Community, I have found that nearly all types of Macs have the problem of updating to macOS Big Sur, including Machintosh HD, 2010 MacBook Pro, MacBook Pro Early 2015, 2018 MacBook Pro, MacBook 2017, MacBook Air, MacBook Pro 16, iMac 2020, and 2020 Intel Mac mini. Besides the installation failed issue, "Update not found" and "Mac apps not opening" are also other big problems.

As always, including macOS, iOS, iPadOS, every new update needs time to be stable and workable. macOS Big Sur update not working problem is no exception, and is also not surprising. But the solution is necessary when any problem occurs.

How to Solve macOS Big Sur Installation Failed Error?

Updated: Luckily, Apple has resolved the server issue causing the unable to download macOS Big Sur problem, by providing the message "macOS Software Update – Resolved Issue. Users may not have been able to download macOS Software Updates on Mac computers".

However, it seems that doesn’t end the complaints. Many users still report the Big Sur install trouble in Apple discussion community.

"Apple Sys Status Now OK…Still won’t update" – asked Smorticula

So, to help you get rid of the headache error notifications, below are some possible solutions. Hope they are helpful.

Method 1. Check if your Mac is compatible with macOS Big Sur

According to Apple, macOS Big Sur can be downloaded on MacBook (from 2015 and later), MacBook Air (from 2013 and later), MacBook Pro (from late 2013), iMac Pro (from 2014 and later), iMac Pro (from 2017 and later), Mac mini (from 2014 and later), Mac Pro (from 2013 and later).

Method 2. Free up your disc space so that you can upgrade to Big Sur

The macOS Big Sur update is only about 12GB in size. However, someone said that you need to have at least 35.5GB of disk space free. After all, another user had reported that his Big Sur download stuck at 12.18GB.

Method 3. Wait a day or two before installing macOS Big Sur

As mentioned above, a new thing always needs time. Though there are betas of macOS Big Sur, the public version will also encounter problems. After learning about all the possible problems and corresponding solutions, you can then feel easy to install macOS Big Sur on your Mac.

In the end, you are highly suggested to back up your Mac before updating to macOS Big Sur.