4-H Online Managers who have County-restricted accounts (usually for a State Fair or Show) may have Fair Manager permissions (or lower), but not Fair Administrator permissions.
If they have been given Fair Administrator permissions, they will get a "Permission Denied" message when they attempt to log in to FairEntry. To fix this, either change their Permission level to Fair Manager or remove the County Restriction.
Briefly, Fair Manager permissions give the manager the ability to see and edit all entries, but not change the fundamental setup of the fair itself. The setup of the fair (entry settings, hierarchy, premium setup, etc.) is restricted to the Fair Administrator role. To learn more about permissions, see Adding Staff Logins and Permissions.