Microsoft: April Windows Server updates cause NTLM auth failures

Microsoft has acknowledged that the April 2024 Windows Server updates are causing NTLM authentication failures and increased load on domain controllers, particularly affecting systems with high NTLM traffic and few primary domain controllers. The affected versions include Windows Server 2022, 2019, 2016, 2012 R2, 2012, 2008 R2, and 2008. Microsoft is currently investigating the issue and has not yet provided a permanent fix but suggests that administrators can temporarily uninstall the updates to mitigate the problem.