Channel meeting invitations are sent to all guest users

Hi 堀田 大輔(hottadai)

Thank you for reaching out to Microsoft Q&A forum

This behavior occurs because a Microsoft Teams team is backed by a Microsoft 365 Group, and that group is likely configured to subscribe to all members (including guests) for calendar events. When you schedule a Channel meeting, it is technically an event for that underlying group.

In this case, I think you could try some of the following workarounds:

1. Create a new group with only internal members, then create a meeting invitation to avoid sending invitations to all members. This is the easiest way to do it.
2. You can try using PowerShell as shown below to forcibly unsubscribe everyone using Exchange Online PowerShell. This requires an IT Admin.

Run this script to remove only Guest users from the subscriber list of that specific group.

$Group = "YourTeamName"
$Guests = Get-UnifiedGroupLinks -Identity $Group -LinkType Members | Where-Object {$_.RecipientTypeDetails -eq "GuestUser"}
ForEach ($Guest in $Guests) {
    Remove-UnifiedGroupLinks -Identity $Group -LinkType Subscribers -Links $Guest.PrimarySmtpAddress
    Write-Host "Unsubscribed $($Guest.Name)"
}

You can try the above approach, kindly let me know in the comments for further support.

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When scheduling a Teams channel meeting, it is indeed the case that meeting invitations are sent to all guest users who belong to that team. This behavior is tied to how Microsoft 365 Groups and Exchange settings manage guest access and notifications. Unfortunately, there is no direct setting in Microsoft Teams that allows you to prevent invitations from being sent to guest users automatically when a meeting is scheduled in a channel.

As a workaround, you might consider the following options:

1. Schedule Meetings in Private Chats: Instead of scheduling meetings in a channel, consider scheduling them in private chats with only the intended participants. This way, only those invited will receive the meeting invitations.
2. Use Meeting Policies: Review the meeting policies applied to your organization. While this may not directly prevent invitations to guests, ensuring that your policies are aligned with your needs can help manage how meetings are conducted and who is invited.
3. Communicate with Guests: If certain guests should not receive invitations, communicate with them beforehand to set expectations about the meetings they will be invited to.

If this issue is causing significant inconvenience, it may be beneficial to monitor the feedback portal you mentioned for any updates or changes regarding guest user management in Teams.

References:

• Guest access in Microsoft Teams
• Guests in the Microsoft 365 admin center