Email flows from external sources to user’s inbox in 365 or alias on inbox in 365, but from on-prem to cloud mailbox email routing fails with following bounce back. You may also see this when scanners or printers from on-prem cannot route email from on-prem to cloud mailbox with error.
NDR with error "Remote Server returned '550 5.4.103 ROUTING.NoConnectorForAddressType; unable to route for address type'" .
One of the reasons you may receive this is due to a wrongly set RemoteRoutingAddress in the RemoteMailbox on premise. To identify and solve this, use the Exchange Shell and run this command:
Get-RemoteMailbox -Identity tim@mydomain.com | Format-List
if the remote routing address is indeed incorrect, use the following command to correct this.
Get-RemoteMailbox <Alias>| Set-RemoteMailbox -RemoteRoutingAddress alias@yourname.mail.onmicrosoft.com
Or from Exchange EMC add the following to address list then set as routing remote mailbox, then wait for sync.
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After doing the above if you receive the following error:
Diagnostic information for administrators:
Generating server: LHG-ExchSRV01.lighthouse.dom
robert.danby@lighthousewealth.co.uk AM5EUR03FT032.mail.protection.outlook.com Remote Server returned '<AM5EUR03FT032.mail.protection.outlook.com #5.4.1 smtp;550 5.4.1 [rdanby@lhgplc.mail.onmicrosoft.com]: Recipient address rejected: Access denied [AM5EUR03FT032.eop-EUR03.prod.protection.outlook.com]>'
Original message headers:
Give Exchange EOP some time to replicate the knowledge change around other EOP servers, then try again.
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