migrated exchange online users are not receiving external emails.(gmail/yahoo)
We have migrated few test users to office 365. However they are not receiving any mails from external.(gmail/yahoo). i am not receiving any NDR from gmail as well. Mx record is pointed to on premise and domain set as authoritative by default. outbound to office 365 Send connector is been created on-premise EAC . could you please help me to figure out the issue?
If it happens for all migrated users, it might be an issue with the connector, usually a certificate related one, so check for that as well. Doing a message trace on O365 side should give you a clue.