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Hi!
I have inherited a settings where our default domain is set to Internal Relay. With this settings Office365 doesn't reject unknown recipients and we get a loop in our Hybrid environment.
All our mailboxes are moved to O365 but we still have Exchange in house.
My questions is if we change our Accepted Domain from Internal Relay to Authoritative then will it create any issue in email delivery or some downtime? Do I have to check something before doing this?
Thanks for your input on this.
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Hi @Anonymous ,
Agree with Andy that you can go ahead make the change.
By the way, if Andy's post was helpful, you can click "Accept Answer" under his reply so that it can be easier for others with similar questions to see the useful information. Thanks!
Are there any mail-enabled objects on-prem? Public Folders? any routing from on-prem Exchange to another mail system?
If not, then its ok to set to Authoritative.
Are there any mail-enabled objects on-prem?
There are two but not in used. We disabled one for testing and it already have a alias in Office365 with a shared mailbox so it works fine. So I will say nothing related that is in use.
Public Folders?
I found few but not in used.
and routing from on-prem Exchange to another mail system?
can you tell little more about this?
Thanks
If you have a shared mail space like unix or something similar. Email Addresses that arent in 365. If not, then you are good!
No such thing. We only have unix smpt server pointing direct to O365.
Will it be any downtime of emails when we change the settings? I am not able to find much info about what will happen in the background when you change this settings.
No downtime. As soon as the change takes effect, any future emails sent to non-existent recipients will simply be rejected at the 365 gateways rather than routed to the on-prem Exchange server which then rejects them.