Forum Discussion
Exchange Hybrid - On-Prem mailboxes can't send to Online mailboxes
We're now running Exchange Hybrid OnPrem: Exchange 2019 latest patch. On-Prem mailboxes are not able to communicate with mailboxes in Exchange Online in any way. The other way around is working ...
Hello,
It seems that your public IP address has been greylisted by Exchange Online environment. You can try to change your outgoing mails public IP address to confirm. However this change also requite to review the connectors and SPF as well.
You can also add your Public IP addresses to the Exchange Online Protection whitelist.
Thanks
Srikant
It seems that your public IP address has been greylisted by Exchange Online environment. You can try to change your outgoing mails public IP address to confirm. However this change also requite to review the connectors and SPF as well.
You can also add your Public IP addresses to the Exchange Online Protection whitelist.
Thanks
Srikant
