Teams is no longer sending invite emails

Hi @Andrew B, 

Thank you for posting your question in the Microsoft Q&A forum.  

The issue described is that Teams is no longer sending meeting invitations after your Microsoft 365 subscription was reactivated. 

When a subscription is suspended and then reactivated, certain service plans and tenant settings may not fully re‑enable in sync. Teams relies on Exchange Online for calendars and for generating the email invitation message that goes out to attendees. Even if your MX records point to a non‑Microsoft mail host, the Exchange Online service plan still needs to be enabled for the organizer so Teams can create the meeting, place it on the calendar, and send the invite email through Microsoft’s mail service. If Exchange Online is off for the user, or if email notification settings were reset, invitations will not be generated or delivered.

Below are some workarounds that suit your situation: 

1/ Begin by using the Paste Special feature to confirm your license and service plans. 

• In Microsoft 365 Admin Center, verify your subscription is active. 
• Admin center → Users → Active users → select the user creating meetings 
• Licenses and apps → ensure a license that includes Microsoft Teams is assigned 
• Under the same license, make sure both Microsoft Teams and Exchange Online Plan 1 or Plan 2 are turned On 

Note: This does not move your MX records or make Microsoft 365 your email host. It only enables the mailbox and calendar integration that Teams uses to send invites. 

2/ Then, verify that your mailbox and domain settings are correctly configured. 

• In Exchange Admin Center → Recipients → Mailboxes → confirm the organizer’s mailbox is active. 

• Entra admin center → Identity → Custom domain names 
• Ensure your domain shows Verified, not Pending 

If the billing hold caused any domain verification to slip, Teams will not send invites from that domain. 

3/ Proceed by turning on email notifications within your Teams settings. 

• Go to Teams Admin Center → Teams settings → Email integration. 
• Make sure Send email is enabled. 
• If you use Teams meeting templates or custom policies, review the applied Meeting policy to ensure email reminders and scheduling are allowed 

4/ After that, test the configuration and validate that everything is functioning as expected. 

• Create a test meeting and check if the invite appears in Sent Items. 
• If internal invites work but external ones fail, review SPF records to include spf.protection.outlook.com for Microsoft 365 mail authentication. 

5/ Finally, trace the messages using the Exchange Admin Center to identify any delivery issues. 

• Exchange admin center → Mail flow → Message trace 
• Search by the organizer’s address and the test meeting subject 
• Review the Status 

Delivered means the invitation left Microsoft successfully. If external recipients still do not see it, ask them to check Junk, quarantine, or security gateways 

Deferred or Failed usually indicates a recipient side block or a DNS authentication issue 

6/ For a more efficient resolution, we recommend using your administrator account or contacting your IT administrator to submit a support request directly to Microsoft Support team.  

They can raise a support ticket by visiting: Get support - Microsoft 365 admin | Microsoft Learn 

Please understand that our initial response does not always resolve the issue immediately. If you continue to experience difficulties, please feel free to attach a screenshot. This will help us better understand the issue and provide more accurate assistance. However, with your help and more detailed information, we can work together to find a solution.  

I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.  

Thank you for your patience and your understanding. If you have any questions, please feel free to reach out.  

I'm looking forward to your reply.

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