This hotfix, and Pro Tools 10.3.10 itself, was designed for a specific era of Apple hardware and software. If you're running it on an unsupported system, you will likely encounter errors, crashes, or the software may fail to launch entirely.

: Avid officially states that Pro Tools 10.3.10 is not qualified for macOS 10.9 (Mavericks) or higher, though the R3 hotfix is often used to bridge this gap.

Before modifying any core DAW files, back up your current working environment.

10.3.10 is a full installer . Avid recommends a "Clean Uninstall" of any previous Pro Tools versions before proceeding with the installation . Legacy Support Context

: Avid recommends a clean uninstall of any previous Pro Tools versions before applying 10.3.10. Installer Access