Features that support communication and collaboration between schools and families
The account shown as ...#EXT#@csdma.onmicrosoft.com is a “guest” work/school account created by the school’s Microsoft 365 tenant using the same personal email address. It is not something that can be deleted or managed with a separate password; it is controlled by the school’s tenant admin. What can be done locally is:
- Sign out of Teams and remove the account from Teams
- In the Teams desktop app (Windows or web), select the profile picture at the top right.
- Select Sign out.
- Sign back in only with the desired personal account.
Note: Signing out removes the account’s data from the Teams app on that device, but does not remove the account from other apps or from the school’s tenant.
- Leave the school’s Teams organization (if using Teams Free UI)
If the account appears as an organization in Teams Free:- Open Teams (desktop or web).
- Go to Settings → Accounts and orgs.
- Under Organizations, find the school organization (CSDM).
- Select Leave next to that organization and confirm in the browser window that opens.
After a few hours, sign out and back in to Teams; the organization should no longer appear.
- Remove the work/school account from Windows (device registration)
If Windows is treating the device as connected to the school:- Open Settings → Accounts → Access work or school.
- Select the school/work account entry (the one referencing the school) and choose Disconnect.
This removes the work/school account from the device and unregisters it from that organization’s directory for this device.
- If the account still appears as part of an organization
Because the#EXT#@csdma.onmicrosoft.comidentity is created and owned by the school’s Microsoft 365 tenant, only that organization’s admin can fully remove the guest account from their tenant. If Windows or Teams continues to prompt for that organization’s policies after the steps above, contact the school’s IT or technical support and ask them to remove the guest account associated with the personal email address from their tenant.
If the goal is to completely close the underlying personal Microsoft account (the @hotmail.com address) that is used to access Teams and other services, that can only be done after it is no longer tied to organizations or subscriptions, and closing it will also remove access to Outlook.com, OneDrive, Skype, Xbox, and other consumer services.
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