I have configured a Accepted Domain for domain.com and mark it as Internal Relay Domain. Configured a new Send Connector for the address space domain.com and set the External server as the smart host value for delivery. With this configuration, Exchange must deliver any known @domain.com Exchange recipients locally, but must forward email for unknown @domain.com recipients to the external server. and i am having "recipient not found" for some users if their exchange mailbox is disabled. If it is enabled mail delivered to user exchange mailbox locally (user@domain.local) and not forwarded to another host. mostly all mail goes normally, except for some users. smtp configuration for user is user@domain.local only (not ".com"). Be real

If there is an address in the directory, mail delivery is attempted to the recipient. If you don't want that, remove the address.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

hi, The accepted domain that's configured as an internal relay domain first tries to deliver to a recipient in the Exchange organization. If the recipient isn't found, the message is routed to the Send connector that has the closest address space match. Because the transport process resolve recipient from AD, so if you only disable their mailbox, transport process still can resolve the AD user. Then exchange stamps the mailbox status that is unavailable and throw the error out. So i guess exchange will not deliver the message to another host. If you disable the user in AD, mail flow will be normal. thanks,CastinLu TechNet Community Support

disable user in AD is not an option.Be real

already done. still the sameBe real

The solution is to make domain.com EXTERNAL relay domain and domain.local INTERNAL relay.Be real

got it. tnx 2 uBe real