Registers an existing and disabled user, group, or resource for WorkMail use by associating a mailbox and calendaring capabilities. It performs no change if the user, group, or resource is enabled and fails if the user, group, or resource is deleted. This operation results in the accumulation of costs. For more information, see Pricing. The equivalent console functionality for this operation is Enable.

Users can either be created by calling the CreateUser API operation or they can be synchronized from your directory. For more information, see DeregisterFromWorkMail.