Using Classic Outlook on Windows for personal email, calendar, and contact management
Here is another option to manually mitigate the missing Teams Add-in that I have seen work for several internal users.
- Uninstall the Teams Meeting Add-in MSI from Windows Apps > Installed apps:
- Close Outlook and quit New Teams from the Task tray.
- Restart New Teams.
- This will force "New Teams" to reinstall the Teams Meeting Add-in which should fix the issue, once it's running and you see Teams Meeting Add-in in the list of installed apps again, restart Outlook and it should be working again.