After creating an account in the Own Server Setup Wizard this error is displayed.
To fix it make sure the SQL mode is NOT set to strict.
For mySQL – see https://kb.locklizard.com/knowledge-base/error-i-have-protected-a-pdf-but-it-is-not-showing-on-the-administration-system/
For MariaDB run the following query on the LL database:
set global sql_mode=”;
Then restart MariaDB for the new settings to take effect.