No Exchange, você precisa criar um contato smtp habilitado para email e depois, no fluxo de mensagens da conta, encaminhar para o contato desse externo.
How to configure mail forwarding Note The forwarding address can be any mail-enabled object. Examples of mail-enabled objects include distribution groups, security groups, public folders, and other related items.
- Start the Active Directory Users and Computers snap-in.
- Right-click the mail-enabled user, and then click Properties.
- Click the Exchange General tab.
Click Delivery Options.
- In the Forwarding Address section, click Forward to, and then click Modify.
- Click the mail-enabled user or the mail-enabled contact. Then, click OK.
Note If you want e-mail to be delivered to the original mailbox as well as the forwarding address, select the Deliver messages to both forwarding address and mailbox check box. To close Delivery Options and to close Properties, click OK two times.
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