Forum Discussion
External Guests being invited to channel meetings
ongrieh , stevecousins I have been chasing this problem as well. What I have figured out is that behind the scenes of the Team is a MS365 group and all Guest Users are automatically designated as 'Subscribers' of the group, regardless of team setting on "AlwaysSubscribeMembersToCalendarEvents" and "AutoSubscribeNewMembers". I presume this is because they can't directly interact with the Team/Group and self-subscribe or join channel meetings ad-hoc. However, this is not ideal because guests then get invited to _every_ channel meeting without explicitly inviting them.
The only way I can find to remove guests as subscribers is via PowerShell. You can view group/team Subscribers with Get-UnifiedGroupLinks -Identity [team name] -LinkType Subscribers. You should see the Guest accounts listed as 'MailUser' recipient types with #EXT# on the name. You can remove these with Remove-UnifiedGroupLinks -Identity [team name] -LinkType Subscribers -Links [Name]. Allow a few moments for the subscriber list to update.
This does not remove guests from their Member role, but now they won't be email-invited to every channel meeting. I haven't confirmed it yet, but it is possible that Guest Accounts get re-subscribed from some unknown trigger. That plus additional guests getting auto-subscribed necessitates creating a script to routinely unsubscribe guests.
Microsoft should fix Teams to honor "AlwaysSubscribeMembersToCalendarEvents" and "AutoSubscribeNewMembers" on Guest accounts.
I found an alternative solution for this bug, it doesn't depend on administrative privileges or even microsoft's will to definitively fix this bizarre bug, it just depends on the user's own email rules configuration (guest).
This varies depending on the mail server, for example in gmail , ask the user to put the following rule/filter (copy the code below and paste it in the field: "has the words"):
({to:(@domain_of_emails_received_in_groups.com.br) AND to:-guest_mail OR cc:-guest_mail}) {filename:vcs filename:ics}
Then make this filter (rule), mark emails as read + delete them. This will do. Because all invitations that arrive at the guest account, in which the guest is not invited, will be automatically discarded.
If your guest uses an OUTLOOK account, it partially solves the problem. Ask the guest to create a rule in outlook like the print below (you can fill in the domain instead of the group domain):
Why does it partially resolve in outlook? The guest will not receive email notifications of new meetings that do not interest him (who was not invited), however, even if these emails are deleted, outlook keeps the event in the user's calendar with tentative status, so he will receive notifications when you are close to the start of meetings.
If anyone manages to circumvent this other problem. Please let us know.
For other email providers, it works the same: just create an email rule.