Ensure you have at least 15GB to 20GB of free storage space on your primary drive.
: You need at least 12.5GB to 18.5GB of available storage to perform the upgrade.
Change system date temporarily via Terminal:
If you want to ensure a smooth transition, I can guide you through the process. Let me know: What exact do you have? Do you have any essential older software you rely on daily? how to update macos high sierra 10136 to 1015
[High Sierra 10.13.6] ──> [Time Machine Backup] ──> [Download Catalina Installer via Safari] ──> [Run Setup] 1. Create a Time Machine Backup
To check your model, click the in the top-left corner of your screen and select About This Mac . Note the model name and year listed in the Overview tab. Step 2: Check Storage and System Requirements
Once you're logged into Catalina, a few steps will help you finalize the transition. Ensure you have at least 15GB to 20GB
Catalina requires at least , but 30–40 GB is safer.
: Use the built-in Time Machine utility to back up your files to an external drive.
If you're having trouble updating directly, you can try using macOS Recovery: Let me know: What exact do you have
how can I update mac os from High Sierra … - Apple Community
Once the download finishes, the installer will automatically launch on your desktop. Click and agree to the software license terms.