lock(To prevent users from joining a conference, whether or not they have an invitation); block(To prevent another user from initiating a conversation and from viewing your presence or other information, such as your personal information)
Blocked(A privacy relationship setting that prevents a person or domain from adding the user to contact lists, seeing the user's status, or sending instant messages to the user); locked(The condition of a field, record, recordset, or database that makes it read-only to all users except the user currently modifying it)
