A blocked user is added to the Blocked Users list either for a selected Client or for all Clients in the system (depending on your choice while blocking the user).
The Blocked Users list is stored on the Application Server. If you edit the Blocked Users list, the Client will receive this information from the Application Server immediately. In case there is no connection with the Application Server computer (i.e. the Application Server is unavailable), the Client will not block users that are on the blocked user list until the connection is re-established. Once this happens, the Client will receive the latest edited version of the Blocked Users list from the Application Server.