Settings & keep-time · Advanced, self-backup and Demo Mode
Why doesn't my encrypted external drive mount after a restart, and what is the auto-mount notice in Settings?
Short answer: A leftover start-up entry from an earlier version can stop encrypted external drives mounting after a restart. If found, Settings → Advanced shows an auto-mount notice with a button to remove it.
An earlier version of Storage Studio could add a start-up entry that pinned where your drive mounts. On drives encrypted with FileVault, that entry stops macOS mounting the drive automatically after a restart, leaving it unlocked but not mounted.
If Storage Studio finds that leftover entry, Settings → Advanced shows an External drive auto-mount notice with a button to remove it. Removing it asks for your Mac password and restores normal auto-mounting. The drive is still recognised correctly without it.