Reference for macOS Update error codes and their meanings reported in the Automox Activity Log
Error 93: Cannot stage X because an update is already staged to install at next reboot
macOS Security Updates installers do not install immediately, instead they "stage" or "cache" the updater to install at the next boot. When Automox reports in the activity log that these updates are installed, it has successfully staged and will complete installation at the next boot. If you attempt to install the update again through the Automox console, you will receive Error 93 because an update is already cached. To resolve this issue, reboot the device to allow the staged update to finish installation.
All macOS updates requiring reboots
Article is closed for comments.