How to Troubleshoot macOS Sierra Download and Install Problems

Jean updated on Aug 30, 2019 to Mac File Recovery | How-to Articles


Full solutions are available here to troubleshoot macOS Sierra download stuck or failed to install problems with relevant error messages, such as macos sierra cannot be installed on null; this version of macos 10.12 cannot be installed on this computer; macos sierra downloaded but not installed, etc.

Have you updated to the latest macOS Sierra version on your Mac & MacBook? What problems have you met while downloading and installing this macOS 10.12 Update? After days of trial and observation on this new update, we found that a vast majority of Apple computer users encountering a category of macOS Sierra download and install problems with relevant error messages. In a word, their attempts for macOS Sierra update stuck or failed.

Let's see what common problems failed people's attempt to download and install macOS Sierra on their machine, and how to fix the relevant errors efficiently so as to update to macOS Sierra without a hitch.

#1. 'This version of macOS 10.12 cannot be installed on this computer'

This is a compatibility issue if such an error occurs on your computer, and the only fix to the problem is to upgrade your Mac machine to late 2009 or above to meet the requirements. Following are the macOS Sierra supported devices:

  • Late 2009 or newer version of MacBook
  • Mid 2010 or newer version of MacBook Pro
  • Late 2010 or newer version of MacBook Air
  • Mid 2010 or newer version of Mac mini
  • Late 2009 or newer version of iMac
  • Mid 2010 or newer version of Mac Pro

#2. macOS Sierra app is damaged

The full error message should be 'This copy of the Install macOS application is damaged, and can't be used to install macOS'. It's because the update file is either corrupted or was interrupted while you're trying to download and install macOS Sierra.

Try to fix it by deleting the "Install macOS Sierra" file from Launchpad, reboot your Mac and download again the macOS Sierra update file.

#3. macOS Sierra cannot be installed on (null)

You're installing macOS Sierra and it almost completes in about several seconds, however, you have to cancel it because of the error 'macOS Sierra cannot be installed on (null). What a pity! After a long waiting, all you have to do is to do it again.

One way to kill the 'null' error is to restart your Mac machine before going through the installation process.

#4. macOS Sierra is downloaded but can't install

"I have downloaded the macOS Sierra from the app store but unable to install it. It's not displayed in the updates section..."

Some are asking why there is no install option available after the update has successfully downloaded. Actually, you'll have to find the 'Install macOS Sierra' app in your Applications folder.

After downloading macOS Sierra it doesn't appear in the Updates section of the App Store app. Instead, it is downloaded to your disk and usually can be found in Applications. Check the update file there and start to install.

#5. macOS Sierra install slow, stuck or froze

"I'm stuck in the middle of what is either an install or a complete erasure of my hard drive. Can't get rid of it."

"Macbook is very slow after updating to macros sierra. I try to open an app and it is very slow, even finder. How do I fix this?"

"I installed Sierra on my MacBook Pro a few days ago, and several times it has frozen. First, the computer stops responding to my external mouse. About 30 seconds later it stops responding to the trackpad and keyboard. I have to force a restart. Why macOS Sierra keeps freezing?"

The general troubleshooting steps for macOS Sierra update stuck or failed are:

  • Get rid of any antivirus software installed on your Mac. 
  • Make sure you have created a Time Machine backup on hard drive. 
  • Press the power button and hold down the Shift key. 
  • Try updating software in Safe mode. 
  • Switch from wireless connection to hardwired connection.

While to speed up Sierra, follow these steps:

  • Clean up your macOS with built-in disk cleaning software called Disk Utility.
  • Moderate the UI experience by turning off 'heavy effects': go to Apple Menu –> System Preferences –> Accessibility –> Display.
  • Use the new optimized storage upgrade by going to Apple Menu –> About this Mac –> Storage.

#6. Disk formatted and data lost after macOS Sierra update

"Didn't create a Time Machine backup before upgrading El Capitan to macOS Sierra. Unfortunately, formatted the hard disk and lost some very important document files. How to recover?"

It seems that only third-party Mac data recovery software can help restore lost data without a backup. EaseUS Data Recovery Software for Mac fully supports macOS Sierra data recovery due to system update, deletion, disk formatting and virus infection. Go and bring files back by yourself with the detailed guide behind.

Step 1. Select the disk location (it can be an internal HDD/SSD or a removable storage device) where you lost data and files. Click the Scan button.

select the location where data lost and click scan

Step 2. EaseUS Data Recovery Wizard for Mac will immediately scan your selected disk volume and display the scanning results on the left pane.

scan the selected disk to find lost data on your Mac

Step 3. In the scan results, select the file(s) and click Recover Now button to have them back.

click recover now button to recover lost data on your Mac


100% of people found this article helpful.


Frequently Asked Questions

1. Why choose EaseUS Data Recovery Wizard?

"EaseUS Data Recovery Wizard is the best we've seen. It's far from perfect, partly because today's advanced disk technology makes data-recovery more difficult than it was with the simpler technology of the past, but it's fast and efficient..."PCMag

"The first thing you'll notice about EaseUS Data Recovery Wizard Pro is that its interface is very clear and uncluttered, with only a small collection of self-explanatory controls. You won't find lots of extra options hidden in a system of hidden menus, either; what you see really is what you get."techradar

"Recover lost files, even after deleting a partition or formatting your drive."Macworld

2. Why cannot I recover 2GB data for free?

It is recommended to check the version installed is Free or Trial because they are different versions.

Trial has data preview function but cannot save any files, while the Free version enables to recover 2 GB files. The default free space is 500 MB and you may share the product on social media to get another 1.5 GB.

3. Why cannot the recovered files be opened?

A file is saved as 2 parts on the storage device: directory info (which is comprised by file name, time stamp and size info, etc.) and data content.

If the files with original file names and folder structures cannot be opened, one possible reason is the corrupted directory info. There is still a chance to recover the data content with the RAW Recovery method in our software.

4. Why isn't it suggested to recover the files back to the original drive?

The storage structure of the lost files would be altered or damaged by any changes on the drive. If you save the recovered files back to the same drive, the original data structures and data content would be corrupted or overwritten, which causes permanent data loss. So you should prepare another disk to save the files.

5. How can I check whether my data is recoverable or not before purchase?

The Free version helps you save 2GB files, so verify the recovery quality of our product before purchase.

6. How long does it take to scan the drive?

It strongly depends on the capacity of your hard drive and the performance of your computer. As reference,most drive recoveries can be completed in around 10 to 12 hours for a 1-TB healthy hard drive in general conditions.

About Data Recovery Wizard

It's super easy to recover 250+ types of files after deletion, disk formatting and virus infection. Click the links and compare the difference of each version.