Teams invitation emails marked as spam

Question

Hi,

We are using Teams, but we do not use Exchange for our email service, we use Amazon. When I schedule a meeting in Teams, the invitations to external invitees are being marked as Spam and the invitees are not getting their invitations (unless they check their spam folders). Can you please tell me how to stop the invitation emails to external invitees being marked as Spam, when using an email service other than Exchange?

Also, I would like all internal invitees to get email notifications too, as most of them do not use their 365 Calendar as their main calendar. From what I can see, only external Teams invitees get emails, while internal invitees have meetings added to their 365 Calendars (which they miss because they don't use this calendar regularly).

Thanks in advance.

Philip.

Answer 1

Hi Philip,

By default Teams integrates with Exchange Online, thus the meeting invitation email would be sent by the Exchange service.
And if the recipient is internal, the email would be sent to his Exchange Online mailbox.

If you didn't configure SPF,DKIM,DMARC for your domain in Exchange Online, it may possibly be the cause why these emails are marked as Spam by recipients.
Below are links which may be helpful:
Email authentication in EOP
Set up SPF to help prevent spoofing
Use DKIM to validate outbound email sent from your custom domain
Use DMARC to validate email
Or if the emails are only rejected by certain recipients, if possible please contact them or their email service provider to confirm if they can whitelist your domain.

If you would like to have these internal invitation emails sent to Amazon mailboxes instead of Exchange Online mailboxes, you can setup rules to auto-forward the emails to the Amazon mailboxes.
There are several methods:
configure forwarding on a mailbox: Configure email forwarding for a mailbox in Exchange Online
use Exchange mail flow rules (you can either select redirect or add Amazon mailbox to the to/cc/bcc box as action) : Mail flow rules (transport rules) in Exchange Online

Also note that: By default external auto-forwarding is disabled in Exchange Online and you may need to enable it first if you would like to use external auto-forwarding.

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Answer 2

@Kael Yao-MSFT
We have the same issue that the confirmation emails "You are registered for the webinar" end up in spam. Apparently, the emails are now being sent from the address noreply@TENANTNAME.s01.eur1.teams-events.com and there is no SPF and DKIM set up. Do we have to do this as a customer or Microsoft? If we have to do it, can you explain where and how? We do not have access to the DNS settings of this domain.

Answer 3

We're experiencing the same issue, both with internal and external recipients. Our emails are sent from noreply@tenantname.s01.usa1.teams-events.com. Anything else we could check? it's becoming a big problem for us. Thanks!