When using the On Demand Migration (ODM) Domain Coexistence feature, you may experience the following error:
550 5.7.64 Relay Access Denied ATTR36.
原因
This was in a hybrid environment with the MX record pointing to the on-premise Exchange server.
解决办法
In this scenario, users migrated with ODM will need a "Remote Mailbox" created on the on-premise hybrid server in order to point to their Office 365 mailbox for mail routing.
其他信息
ODM does not have the ability to access your on-premise hybrid server to perform this action on your behalf, so this task will need to be performed outside of ODM.