Mac OS FAQ

Patches and Updates

Updated: 18 Sep 2020

1. What is a Patch or Update?

As with any software, bugs can be found or features missing from the orginal software supplied. So, Apple releases a patch which fixes a problem they found or a missing feature, this patch will replace programs and files on your system with newer versions. Before updating you Mac you should always make sure you have a backup e.g. Time Machine.

2. Where can I get the latest Patches or New Build version?

Most patches are available via the Update tab in the App Store tool in the Dock or from the Apple Support website.

Note, that patches are only available for 2-3 years, some security updates are available near end of life. After that, the only way to get more features or security updates is to update to the next version of macOS.
Catalina update 10.15.7


3. I have downloaded a new build for Mac OS but it will not install?

First make sure you have enough room on System disk to save backup files and install the new update. Also, check that your copy of Mac OS version matches the version of the update your have downloaded and they any previous updates may be installed first. A Combo update includes all previous updates, so no previous updates are required first.

4. I have an office or company with lots of Macs, how can I easily deploy patches?

Mac OS Server includes Caching Server, so an update is only download from internet once, and desktop Macs can retreive it from the Mac OS Server.

Alternative, include ManageEngine's Mac Patch Management , Munki , IBM's JamF Pro and Shavik.

5. Can I upgrade to a new version of Mac OS?

Yes, but you need to check that your Mac Hardware is compatible. See About this Mac to see the Make, Model and year of your Mac first and if compatible, you can download the version of Mac OS via the App Store or IsoRiver.com. Download the Mac OS, and it will appear in the Applications folder, you can then run this to upgrade your Mac. Make sure you backup your Mac first and have a copy of the Mac OS on USB or external drive somewhere, in case you need to reinstall your old Mac OS again.

6. Can I uninstall a Patch?

No, you will have to restore your OS disk and applications back from a backup to restore it to a point before installing the patch. Use Time Machine or other backup software to restore to a previous backed up system.

7. Can I install a new version of an app on an older version of macOS?

Maybe but it depends if the app checks to see what version of macos or what libraries or hardware it requires to run.