Microsoft has confirmed customer reports of NTLM authentication failures and high load after installing last month's Windows Server security updates. According to a new entry added to the Windows ...

Microsoft says users might experience authentication issues on Domain Controllers (DC) running Windows Server. after installing security updates released during the November Patch Tuesday.

Microsoft provides detailed update instructions that Exchange admins should follow, including updating the relevant cumulative updates (CU) for Exchange Server 2013, 2016, and 2019.