The GroupWise Address Book lists all users that belong to your GroupWise system. When users receive incoming messages, the senders are added to users’ Frequent Contacts Address Books to facilitate replying to users who are not included in the GroupWise Address Book. If necessary, you can configure GroupWise so that external (non-GroupWise) users appear in the GroupWise Address Book and are therefore available to all GroupWise users. For setup instructions, see Section 11.1, Using a Non-GroupWise Domain to Represent the Internet