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.
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.