You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Upgrade to Catalina.

I have High Sierra late 2013 27 inch iMac. With 999.1 GB available. storage. Can I upgrade to Catalina?

iMac 27″, macOS 10.13

Posted on Sep 24, 2021 11:47 AM

Reply
Question marked as Top-ranking reply

Posted on Sep 24, 2021 11:50 AM

Hello. Your iMac can run macOS Catalina. macOS Catalina is supported on these computers.


If you do not see macOS Catalina as an available upgrade for your Mac in the App Store or System Preferences, you can download the installer for it by using the information on this page.

9 replies

Sep 24, 2021 2:10 PM in response to Catherine2013

The Age of this computer will Govern what newer version of macOS it will Qualify to install. Use About this Mac from the Apple Icon on Desktop - the required Information will be there.


With the above information in-hand - follow this How to get old versions of macOS and verify what version this computer Qualifies to install. Make sure to use Only Safari to commence the download as Others may not work. Safari will open a redirect and open the Apple Store where you can commence the download. If an error message appears, that is probably because one is using another Browser.


Suggest using Go64 to find 32 bit application before attempting the upGrade. Some or many of the Application already installed may required update or upGrades to 64 Bit Versions.


Make a Time Machine Backup Before attempting. Notation - Mojave is the Last version to support 32 bit applications / extensions and Drivers. Catalina & Big Sur supports only 64 bit and there is no workaround.


Are there any AntiVirus, Disk Cleaner, Optimizers, Un-installers, etc installed which should be removed as per Developers Instructions. They are useless, unneeded, cause havoc and interfere with the normal operation of the OS and may even Corrupt the OS requiring a Reinstallation

Sep 24, 2021 12:44 PM in response to Catherine2013

Hello. The download speed depends on your internet plan. The time the update takes to install depends on your computer's speed and hard drive. Based on my experience with macOS upgrades, I would suggest setting aside an hour or two for the upgrade to complete once it starts. Alternatively, you could start the upgrade before bed and let it run overnight.

Upgrade to Catalina.

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