Install an Exchange server for two domains with different domain names

Learn how to set up a single Exchange server for two domains while both domains maintain their individual names.

Q: I have two trusted domains, domain A and domain B. I want to install one Exchange server for both domains, but...

keep the individual domain names for the relevant domain users. For example, domain A users should get their email from and Domain B from Is this possible?

A: You need both domain name system (DNS) MX records to point to the front-end servers for your Exchange implementation. Then you need to define multiple recipient policies that establish appropriate proxy addressing for each domain. Because you said each Exchange server services only one domain, your Recipient Update Service (RUS) settings could include the server that the mailbox is housed on, as the rule to define which person gets which proxy address

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