Microsoft Teams email server

Copper Contributor



I'm having an issue that I'll try to explain in few steps:

1. Our company has O365 Business Standard licenses.

2. We are using our own locally hosted mail server.

3. By default, when creating Teams meeting, mails would be sent from "". Our boss didn't like that, as people are unable to reply to it and he wants it to me be sent from our domain.
4. I've tried fixing issue by adding our domain to tenant, but now there is no mail sent at all. In logs it is possible to see that he tried to send mail by Microsoft Exchange but it is not possible since no settings regarding mail dns and other stuff were set (everything is still pointing to our local mail server) and I can't change that since employees that don't use O365 at all would lose mails.

My question is, does anyone have any idea how can we force Teams to send email invites with our mail server and/or domain (not without fully transferring email to Microsoft Exchange ?


Thanks a lot in advance !

2 Replies
Is that "locally hosted mail server", Exchange Server?

@DusanGligoric my guess from your description is that you have both on premises mailboxes and mailboxes in Exchange online associated with your Teams accounts, the 'unable to reply' is because it's not coming from the mailbox your users are using.


Assuming your local server is Exchange, you need to configure it so that Teams can access it over the internet, it's relatively complex to do but instructions are here How Exchange and Microsoft Teams interact - Microsoft Teams | Microsoft Learn.


In general it's simpler to set up Exchange Hybrid between local server and Exchange Online, which is also the first step towards migrating email. Teams doesn't need you to migrate, but it really should be your longer term roadmap. Create a hybrid deployment with the Hybrid Configuration wizard | Microsoft Learn


If your local server isn't Exchange Online then you are simply out of luck.