Only meeting organizers can make changes (Shared Mailbox)

[psantus]

When a user creates a new meeting from a shared mailbox calendar (Outlook), it seems they can't edit the Teams meeting options.

When they do, they face the following error: "Only meeting organizers can make changes"

[#2]

@timstevenson 

I have tried assigning both an Exchange plan 1 and an Office 365 E1 licence to the underlying user, with no positive outcome.

[#3]

For what it's worth, we have resolved this in our company by making the users also owner of the Calendar.
Add-MailboxFolderPermission -Identity "sharedmailboxaddress:\calendar" -User usermailaddress -AccessRights Owner

Seems to work afterwards, but only when they are working from Office or connected through VPN when working from home, even though the mailboxes are O-365 hosted and not On-Prem.

[#4]

This issue can be fixed, if you don't use automapping for those shared mailboxes. We disabled automapping for some users in one mailbox, connected it manually into Outlook, and the issue was fixed.

[#5]

@Zantas I have tried this but still not working, can you give any more details, does it still have to be the person who organised the meeting or can you add anyone in as owner and update the meeting options.  Is there a particular way to access the meeting options?

[#6]

@chrismai This is entirely possible to get working - Our team has spent a few days on this with MS support and got nowhere, but managed to find a fix.   

1) Enable the AD account for the shared mailbox  (by default these are disabled and I believe this is 99% of the problem)

2) Grant the user full access to the mailbox

3) Grant the user Owner level permissions to the :\calendar folder in the mailbox via powershell:

add-MailboxFolderPermission -Identity "sharedmailboxaddress:\calendar" -delegateemailaddress -AccessRights Owner

4) Wait 24-48 hours.  Within a couple of days, it'll start working.

I also found a temporary workaround for this:

1) Get the user to create a blank calendar entry in their calendar first.

2) Copy the blank entry from their calendar to the shared calendar (drag and drop in Outlook)

3) Open up the copied entry, and edit is as usual.  The meeting options will be available.

Hope this helps.

[#7]

@Beavis667 

Hi the workaround only works for the original creator of the meeting (since the Teams meeting belongs to them) and won't work for any delegate of the shared mailbox.

I'll give a try to your first solution.

[#8]

@psantus Exactly right, but it means at least one person can do something with the meeting options, which is better than zero.   It'll get people up and running while waiting for the main fix to apply, which as we found took up to 2 days to replicate around the MS back-end.

[#9]

I saw the updates here from recent comments and got excited. There's definitely been some (undocumented, unannounced) progress from Microsoft around exposing the Meeting Options (for meetings where the Shared mailbox is the organizer) to the co-organizers, during the meeting, in the Settings menu. However, the solution is still not very good. There are some MS Learn pages which are a little misleading, and I'll share them here, highlight those points now:
https://learn.microsoft.com/en-us/microsoftteams/troubleshoot/meetings/teams-meeting-with-shared-mai...
This page states this fun little hint:

The real truth is that you HAVE to add the Shared mailbox via File > Add Account, or EVERYTHING ELSE is impossible.  It should just state that this is the required way.

Next:

Manage meeting attendance reports in Microsoft Teams - Microsoft Support

The real truth here is that you can never schedule that meeting via Teams, if the Shared mailbox is a disabled account, which cannot be used to login to any Teams app (desktop/web/mobile).  However, at the top of the page from the first link above:

The guidance is that we shouldn't need to, and are advised not to enable the Shared mailbox (which is what we're all after here in the first place!).

Essentially what we have here is A) Microsoft Support, B) MS Learn pages, and C) various comments in various forums from MS customers who've uncovered workaround X, Y, and Z, which almost work but come with a slew of shortcomings, all adding up to false hope and confusion for customers who just want to organize some Teams meetings using some non-human account so that no one person has to openly be the organizer.  Things like events, or larger meetings, etc.

Very frustrating.  Very misleading.  Way overdue to be working.  Something must be doable here without needing to setup a username/password for some non-human account.  All the security advice from any good source agrees with this.