How to prevent (restrict) users from sending mail to a group in the address book

1. Open the Domino Directory
2. From the Groups view, highlight the specific group that should be hidden.
3. Right-click and select Document Properties.
4. On the Security (key) tab, uncheck "All readers and above."
5. Place a check mark next to any users who should see the Group document. Users not selected will be unable to see that particular group in the Groups view.

Unauthorized users will not be able to see the group when looking in the Domino directory or when selecting from the directory when addressing a new memo.

The restrictions apply to messages sent to either a group's Notes address or its Internet address and to messages originating from a Notes client. They also apply to messages sent and received over SMTP (as from an IMAP or Notes client).

From a Notes client, a user who does not have permission to use the group receives an error when attempting to send mail to the restricted group. If the same user attempts to mail from a POP3 or IMAP client, the router generates a non-delivery report indicating that the sender is not authorized to send mail to the specified recipient.

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