Hello.

i have an issue when configuring Exchange hybrid deployment in my environment.

when i complete the Exchange hybrid wizard and OAuth is finished our exchange environment will not receive emails from the "internet" as in senders outside the company.

mail will can be sent out and will flow between internal users.

when i check the message trace on 365 the emails were failing with the following error.

Users were also getting a bounce back saying 

Diagnostic-Code: smtp;550 5.4.1 [user@domain.com]: Recipient address rejected: Access denied

i wondered if it had anything to do with the MX record on our public DNS, i changed this to the one recommended by O365 domain DNS assistant, but this made no odds,

it looks like it could be a receive connector issue however i am new to exchange so i am still learning.

the only way to fix the issue was to run Remove-Hybridconfiguration on the Exchange 2013 server, when this finished and few moments had passed mail began being received from the internal again.

Any Suggestions on what could be caused 

many thanks

Hello.

i have an issue when configuring Exchange hybrid deployment in my environment.

when i complete the Exchange hybrid wizard and OAuth is finished our exchange environment will not receive emails from the "internet" as in senders outside the company.

mail will can be sent out and will flow between internal users.

when i check the message trace on 365 the emails were failing with the following error.

Users were also getting a bounce back saying 

Diagnostic-Code: smtp;550 5.4.1 [user@domain.com]: Recipient address rejected: Access denied

i wondered if it had anything to do with the MX record on our public DNS, i changed this to the one recommended by O365 domain DNS assistant, but this made no odds,

it looks like it could be a receive connector issue however i am new to exchange so i am still learning.

the only way to fix the issue was to run Remove-Hybridconfiguration on the Exchange 2013 server, when this finished and few moments had passed mail began being received from the internal again.

Any Suggestions on what could be caused 

many thanks

Make sure the accepted SMTP domains in the Office 365 EAC are set to Internal Relay rather then Authoritative.

would i need to set all 3 to internal relay or just the on-prem domain that's top in the list?? they are currently all set to authoritative. as seen below

baring in mind that no users are migrated to O365 yet this is just the initial configuration that is causing the issues

• Edited by BpdZenithLtd 8 hours 33 minutes ago

Your *on.Microsoft* accepted domains need to be authoritative. Those are tied to Office 365

Any on-prem SMTP domains should be set to internal relay unless you are confident that DirSync from on-prem to O365 is correctly synching *all* SMTP proxy addresses. Since you are getting that error, and until that is set and working as expected, set your on-prem accepted domains to internal relay. ( Or just leave them as internal relay permanently)

thanks ill give that a go and report back.

Gordon

would i need to set all 3 to internal relay or just the on-prem domain that's top in the list?? they are currently all set to authoritative. as seen below

baring in mind that no users are migrated to O365 yet this is just the initial configuration that is causing the issues

• Edited by BpdZenithLtd Friday, April 10, 2015 10:52 PM

Hi Gordon,

Is there any update?

In addition, I also recommend you post this in Office 365 forum.

Best regards,