New Teams meeting add-in is missing from outlook

We have configured the rule for publishers.

Test everything for yourselves of course, because it seems like Teams changes from week to week.

With recent versions of new Teams, you no longer need both versions of Teams installed to have the Meeting add-in in Outlook.

Both new and classic Teams include the Meeting add-in (but different versions). However, on a computer with both new and classic Teams installed, the add-in will be de-registered when classic Teams is uninstalled and as a result, unavailable in Outlook.

By de-registering the add-in, I mean that uninstalling classic Teams changes the registry entries at:

	HKEY\_CLASSES\_ROOT\CLSID\{19A6E644-14E6-4A60-B8D7-DD20610A871D} 

	HKEY\_CLASSES\_ROOT\TeamsAddin.FastConnect\CurVer 

	HKEY\_CLASSES\_ROOT\TeamsAddin.FastConnect.1\CLSID 

	HKEY\_CLASSES\_ROOT\TypeLib\{C0529B10-073A-4754-9BB0-72325D80D122} 

	HKEY\_CLASSES\_ROOT\WOW6432Node\CLSID\{19A6E644-14E6-4A60-B8D7-DD20610A871D}

This is unfortunate, because like many other organizations, we have added new Teams to computers that still have classic Teams installed, but are now concerned that the add-in will disappear from Outlook whenever classic Teams is uninstalled (which standard users can do from Add & Remove Programs, or Microsoft may do in the future).

Microsoft posted some steps that end users could follow to repair the missing Meeting add-in here: https://support.microsoft.com/en-us/office/teams-meeting-add-in-is-missing-in-outlook-desktop-after-updating-to-new-teams-f1dfc3e7-8f48-4320-823b-e13a5aca60c3

What I would really like to see is that 1) installing or even just using new Teams updates the Meeting add-in to the one that comes bundled with new Teams, and 2) the uninstaller for classic Teams leaves the Meeting add-in alone.

Thanks!

Here are the steps to bring back Outlook add-in, no admin needed.

1. Make sure Outlook and New Teams are closed and not running in the background
2. Navigate to the official download page for Microsoft Teams Download Microsoft Teams Desktop and Mobile Apps | Microsoft Teams
3. Scroll all the way down to Frequently asked questions
4. Expand all
5. Download and install the classic Teams app
6. When Teams classic opens, click the upgrade later option
7. Open Outlook and confirm add-in is working
8. Close Microsoft Teams classic
9. Open Microsoft Teams new version
10. Done, everything should be working now

Optional step: Delete all Teams Classic version icon or train user not to use that version. You need to keep both versions install.

The following solution has worked for us:

1. create Applocker exception for MicrosoftTeamsMeetingAddinInstaller.msi
2. close Teams via system tray
3. close Outlook
4. uninstall Teams Meeting Addin
5. start teams 2.0 - then "microsoft teams meeting add-in for microsoft office" appears in the installed apps
6. start outlook

unfortunately we do not have a solution that we can distribute on a large scale via sccm/intune. however, we have also noticed that the problem has only occurred sporadically and hope that the applocker exception will solve the problem before the big rollout. at the moment both teams are distributed.

@Robpere

We are looking for a permanent fix to this problem.
One possible solution is to let the New Teams complete the Teams Meeting Add-In (TMA) MSI installation on a per-user basis after a user logs on and launches the New Teams app (with the destination folder being %localappdata%\Local\Microsoft\TeamsMeetingAddin).

-TMA MSI is part of the new Teams MSIX so no additional download is needed.
-Outlook should be started after this completes so if Outlook is set to auto start on launch this may need adjustment

-Any security settings blocking MSI installations should be configured to allow the TMA MSI (e.g. AppLocker needs to exclude MicrosoftTeamsMeetingAddinInstaller.msi)

Does this sound compatible with your VDI environment?