Recently, a user asked if I knew why a few user accounts were being removed from a Teams team. I cracked open Purview and fired off an audit search to see what I could find.
Example of the search inputs:
Keyword Search: GUID of the Teams team (you can get this from the Teams admin center or by selecting the three dots to the right of the team name and selecting get link to team, the link has a groupId= value, which is the GUID)
Activities – friendly names: Added members, Removed members
Start: ~90 days back
End: end of today
Search name: something that makes you happy
Start the search and come back after a coffee break. With the search results open, you can see what took place and what process removed the user from the Team.
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- This is the answer to the original question. It appears a Service Principal removed the account from an AD group. Clicking on the row reveals exactly what process performed the action. In my case, this is an Azure Runbook that cleans up teams permissions.
- Microsoft Teams Sync is the workhorse that handles syncing membership to or from the Active Directory (Entra) group associated with the team.