By default, users are not allowed to create chat rooms. However, you can enable this functionality for all users, for a user policy, or for a certain user.
In the GroupWise Admin console, navigate to Messenger > MessengerService, select either the default policy (all users), a user policy (users governed by the policy), or a user, and then click Properties.
Select Allow users to create chat rooms.
Click Save.
Restart the Messaging Agent to make the option visible to users.