This is the most important change between High Sierra and Catalina.
Click and follow the on-screen instructions to complete the installation.
Upgrading from macOS High Sierra 10.13.6 to macOS Catalina 10.15 is a significant jump. It moves your Mac into a modern era of features like Apple TV, Podcasts, and enhanced security, but it also marks the end of support for older 32-bit apps. Follow this guide to ensure a smooth transition. Step 1: Check Compatibility how to update macos high sierra 10.13.6 to 10.15
The installation process may take some time, depending on your Mac's specifications and the speed of your internet connection. Here's what you can expect:
This is the most critical check you can perform. . If you rely on older software—like certain Adobe Creative Suite programs or Microsoft Office for Mac 2011—they will stop working entirely after the upgrade. This is the most important change between High
. Check your critical apps for 64-bit compatibility before proceeding. Apple Support Community Step 2: Prepare Your Mac
Press return and enter your administrator password. Once the Terminal process is complete, you have a bootable installer. To use it, restart your Mac while holding down the key, select the USB drive as the startup disk, and follow the installer's instructions to proceed with the installation. It moves your Mac into a modern era
According to Apple's official specifications, your Mac is compatible with macOS Catalina if it is one of the following models:
, you must first verify your hardware's compatibility and then manually download the installer via the App Store, as it won't appear in the standard "Software Update" window. Step 1: Check Compatibility
High Sierra stopped receiving security updates in late 2020. Catalina continued receiving updates until mid-2022. Today, both are technically obsolete. The most secure macOS is Ventura or Sonoma – but your 10.13.6 Mac likely doesn’t support those. If security is paramount and you can’t upgrade hardware, consider a lightweight Linux distribution instead.
Since you are jumping a full version (from 10.13 to 10.15), this is a significant update. Use Time Machine or an external hard drive to back up your files. If anything goes wrong during installation, you can restore your Mac to its previous state.