My 2009 iMac 21.5" will not upgrade past High Sierra 10.13.3 and I was told my computer would be able to run on High Sierra 10.13.6. It will download from the App store but will not finish installing this upgrade. What is wrong with this Upgrade ?

My 2009 iMac 21.5" will not upgrade past High Sierra 10.13.3 and I was told my computer would be able to run on High Sierra 10.13.6. It will download from the App store but will not finish installing this upgrade. What is wrong with this Upgrade ?

iMac 21.5", macOS 10.13

Posted on Feb 27, 2019 2:35 PM

Reply
Question marked as Top-ranking reply

Posted on Feb 27, 2019 3:38 PM

Download the macOS 10.13.6 combo update, and try applying that.


If that fails and if you have anti-virus or anti-malware or a cleaner or an add-on firewall, remove that per the vendors' instructions, reboot, and try applying the combo update again.

1 reply

This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

My 2009 iMac 21.5" will not upgrade past High Sierra 10.13.3 and I was told my computer would be able to run on High Sierra 10.13.6. It will download from the App store but will not finish installing this upgrade. What is wrong with this Upgrade ?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.