Microsoft resolved an authentication issue related to Credential Guard on systems using the Kerberos PKINIT pre-authentication protocol, affecting Windows 11, version 24H2, and Windows Server 2025. The problem involved improper password rotation when using the Identity Update Manager certificate, leading to user authentication issues primarily in enterprise environments. Devices failed to change passwords every 30 days, causing them to be perceived as stale, disabled, or deleted. The resolution was provided in April 2025 through Windows security updates, and Machine Accounts in Credential Guard were temporarily disabled. Microsoft advised users to install the latest updates for improvements and fixes. This is not the first authentication issue Microsoft has addressed; previous challenges occurred in November 2022 and November 2021, involving Kerberos sign-in failures and delegation scenarios.