Summary
This hotfix replaces Live ID authentication with the OAuth authentication protocol in the Move-CsUser cmdlet. This change provides a more secure and widely accepted authentication mechanism in Microsoft Lync Server 2013 to move user accounts to TeamsOnly and back to on-premises.
Resolution
To get this update, install the September 2021 cumulative update (5.0.8308.1149) for Lync Server 2013, Core Components Server.
Prerequisites
To install this update, you must have .NET Framework 4.7 or a later version installed. Version 4.7 is configured to use TLS 1.2 as the default protocol. TLS 1.2 is required to connect to Microsoft 365 in order to move user accounts.
For more information, see the following Microsoft Learn articles: