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+## Inviting additional OpenID users
+
+Enabling OpenID lets any Authelia user on the instance *authenticate*, but
+ActualBudget still gates actual access separately: only the account that
+completes the very first OpenID login becomes the server owner. Every other
+Authelia user has to be invited from inside ActualBudget before their login
+is accepted — Authelia successfully authenticating them isn't enough on its
+own, and the failure looks the same as a config problem if you don't know
+this step exists.
+
+To invite one:
+1. Log in as the owner account (the one that did the first OpenID login).
+2. Click the **"Server Online"** indicator — the user-management screen only
+   opens from there, not from the general Settings page, which is easy to
+   miss.
+3. Invite the new user by the **exact email address** set for them in
+   Authelia's `config/users.yml` — ActualBudget matches the OpenID identity
+   to an invited member by email, so any mismatch (typo, casing, different
+   domain) fails silently the same way as not being invited at all.
+4. Have them log in via OpenID again.