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Teams Channel Meetings Available to all Members
Updated 23-Dec-2023
I wrote about who receives invitations for Teams meetings in March 2020. Looking back, that was at the start of the Covid-19 pandemic and the massive upsurge in online meetings and usage that propelled Teams to its current level of 300-plus million monthly active users. In any case, people were very interested in figuring out who receives invitations to meetings, and the article is very popular.
A recent question noted that “despite scheduling a Channel meeting, all people that belong to the channel still get an invitation email and the block on the calendar to the meeting created.” The question is why did team members receive invitations?
Apart from discussing the mechanics of creating meetings, Microsoft’s documentation isn’t much help about invitations sent for Teams channel meetings, so let’s probe further. As you’ll recall, Teams supports private meetings created by users with a defined participant list and channel meetings that are open to anyone in the team to attend. When you create a meeting and add a channel, you can specify if team members should receive invitations that add the meeting to their calendar (Figure 1).

If you select the option to send personal invites, Teams generates meeting invitations and sends them to all team members. Going back to the original question, it could be that this is what happened and the user simply forgot that they had asked Teams to notify the other team members.
The Group Subscriber List and Teams Channel Meetings
But life isn’t simple and the obvious answer probably doesn’t apply. Every team has an underlying Microsoft 365 group. Each group has a subscriber list composed of members who want to receive details of messages and events sent to the group. This functionality is directed at Outlook groups, which communicate via email, rather than team-enabled groups, which use channel conversations instead.
By default, the group’s AutoSubscribeNewMembers setting is set to False for team-enabled groups. This tells Exchange Online to not add new users to the group’s subscriber list when they join. However, it’s possible that groups which started out as Outlook groups before they became team-enabled have AutoSubscribeNewMembers set to True, meaning that new users join the subscriber list and receive updates for events like invitations to new Teams channel meetings.
Checking Teams that Auto-Subscribe New Members
To discover if auto-subscription of new members happens for the teams in your tenant, run this PowerShell code:
Connect-ExchangeOnline [array]$Groups = Get-UnifiedGroup -ResultSize Unlimited -Filter {ResourceProvisioningOptions -eq "Team"} If ($Groups) { [int]$i = 0; [array]$GroupNames = $Null ForEach ($Group in $Groups) { If ($Group.AutoSubscribeNewMembers -eq $True) { Write-Host ("Team {0} autosubscribes new users" -f $Group.displayName) $i++ $GroupNames += $Group.displayName } } Write-Host ("{0} teams of {1} autosubscribe new users found ({2})." -f $i, $Groups.count, ($GroupNames -join ", ")) }
Much to my interest, I discovered that 57 teams in my tenant auto-subscribe new members. Many of the underlying groups date back to the earliest days of Office 365 groups and were subsequently team-enabled since.
I suspect that auto-subscription is the root cause for the reported problem. If this is true, the easy fix is to reset the AutoSubscribeNewMembers setting for the affected teams to False and remove users from the existing subscriber list. This code does the job and makes sure that channel meeting invitations only go to team members if explicitly chosen by the meeting organizer:
$Teams = $Groups | Where-Object {$_.AutoSubscribeNewMembers -eq $True} ForEach ($Group in $Teams) { Write-Host ("Resetting autosubscription setting for {0}" -f $Group.displayName) Set-UnifiedGroup -Identity $Group.ExternalDirectoryObjectId -AutoSubscribeNewMembers:$False [array]$Links = Get-UnifiedGroupLinks -Identity $Group.ExternalDirectoryObjectId -LinkType Subscribers Remove-UnifiedGroupLinks -Identity $Group.ExternalDirectoryObjectId -LinkType Subscribers -Links $Links -Confirm:$False }
Another Approach for Teams Channel Meetings
If you don’t want to remove subscribers from groups, another solution exists. You can create a private meeting in Teams or Outlook (with at least one participant). After Teams creates the online details for the meeting, copy and paste the link to the call along with other details of the meeting into a channel conversation (Figure 2). At the appointed time, any members who want to join the call can click the link to connect.

The advantage of this approach is that it works for any kind of channel – regular, shared, and private (the meetings won’t show up in the calendar app). The technique relies on the fact that you’re posting details of a private meeting into a conversation. People who want to attend have the option of copying the details into their calendar so that they’ll be reminded of the call.
All of this proves that Teams is built on a foundation of other services and that sometimes those services are the reason why something unexpected happens in Teams. It also proves that there’s often another way to accomplish a task. Which is kind of nice.
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the ‘Invite members’ radiobutton looks like a new (very welcome) feature. I don’t see it in my tenants yet.
I used the Invite Members button in the Teams 2.1 client…
Do you know when is this Teams 2.1 client going live?
Very soon…
Is that “Invite Members” option really about the client only? I have it in use but still there’s no such option when making a channel meeting. What else could be missing?
It’s now called “Send personal invites”…
Unfortunately, it looks there is still something else going on, at least in our set-up – the channel in question is still sending out invites and blocking the period in their personal calendar for all members. I can obviously stop the actual invites by unticking ‘require response; but it still blocks out the members’ calenders. There’s a lot of people requesting this on Voice and the forums and I think a lot of them are more looking for a way to log an Event rather than a meeting, i.e. something that everyone can see on the channel calendar but does not require attendance. I thought the new send personal invites toggle would have been the solution to this but unfortunately it doesn’t appear to do anything at all on initial testing.
Same here. Do you still use hybrid mailboxes by any chance? We do, and when I tested, the behavior was widlly different between mailboxes hosted online and on premises:
– On premises mailbox receive regular meeting invitations that look and work just like regular personal meeting invitations.
– Mailboxes hosted online don’t get personal invititations to their inboxes. Instead, they see the event in the inbox of the team’s group inbox (in the Groups tab in Outlook Web), but nowhere else. I think this is the expected behavior.
I don’t have any hybrid mailboxes to test against. It doesn’t surprise me that different results are seen with cloud and on-premises mailboxes. A lot depends on the exact configuration used in an organization.
Ah, seems a bit different again then. We are purely cloud based for mailboxes, always have been.
Without seeing the exact configuration of your tenant and how people use channel invitations, I really can’t say where the differences might lie. If you’re concerned by the issue, you could file a support incident and ask Microsoft Support to check. They can examine what’s happening in your tenant. I can’t.
Yes, I did so and nothing changed – the outcome of the ticket was just listed as ‘no issues found’. Ah well, I’m sure another solution will come around at some point or it will randomly be fixed one day
We’ve got the same issue, looks like there’s another property not documented above, give it a try.
AlwaysSubscribeMembersToCalendarEvents : True
AlwaysSubscribeMembersToCalendarEvents controls if group members receive copies of calendar events. If true, they do. If false, they don’t. If you want people to receive copies of all calendar events created or updated in the group calendar, you’d set AlwaysSubscribeMembersToCalendarEvents to True.
Sorry, I am less familiar with the command-line side of Admin, how do I check if this property is currently active and is this command specific for the team/channel or is it a global entry as we wouldn’t want this changed for everyone in every Channel.
So this is interesting as I have done some testing in our Office365 environment (no hybrid).
I’ve created a test Team through the admin portal, added myself and one test accounts. I created a shared calendar on the general channel, and created two events, one with the slider enabled, one disabled. The behavior for the events were identical – both appeared on all user’s personal calendars AND the group calendar. I’ve also checked the AutoSubscribeNewMembers, which was set to false. I am going to circle back with MS and see, as this is not the intended behavior.
Ah great, thanks Matt – glad someone else has been able to confirm this, hopefully get some answers.
I think you also need to toggle the ‘Alwayssubscribememberstocalenderevents’ config to FALSE.
Then wait an hour or two for it to take effect before adding new member and creating the test invite.
Because the script explicitly removes group members from the subscribers list, there are no subscribers to receive calendar or other updates. Then setting AutoSubscribeNewMembers to False prevents new members joining the subscriber list.
AlwaysSubscribeMembersToCalendarEvents controls calendar event subscriptions for new members. And as the documentation says, “The AutoSubscribeNewMembers switch overrides this switch.”
Hi Tony, I’ve been playing arround with the PS scripts you included in your post.
Maybe I’m doing something wrong but, eventhough your script to list groups with AutoSubscribeNewMembers set to True works seamlessly in my tenant and it will list 2 groups, when I run the second one to set all groups AutoSubscribeNewMembers to False nothing happens.
Basically the first line returns no objects so the script stops there.
Thank you
Josu
I just checked and the code ran without a problem. Are there two objects in the $Groups array after the first snippet?
No, there aren’t.
So there are no groups that the script can find to update those settings, which is the reason why you don’t see the settings being updated. Try setting the properties of a group to autosubscribe new members and see what happens.
Set-UnifiedGroup -Identity ‘Group to test’ -AutoSubscribeNewMembers:$True
Even if the AutoSubscribeNewMembers is set to False and no Subscribers links are present, it will still send emails to all of the members of the channel.