A few days ago, Microsoft confirmed that it has fixed a long-standing reported bug in BitLocker encryption “65000” in Windows Intune. These types of issues can often affect a large number of systems when deployed on managed devices in organizations.

Yesterday, Microsoft confirmed a new issue for Windows Server domain controllers (DCs) as it warned that IT and system administrators may notice a large increase in NTLM authentication traffic. The tech giant confirmed that this increase was caused by a bug in the latest April 2024 patch on Tuesday (KB5036909) for Windows servers, and it affects all server OS versions, from 2008 to the latest Windows Server 2019 and 2022.

Windows NTLM, or New Technology LAN Manager, is a suite of security protocols that help authenticate and authenticate users, and it’s something Microsoft wants to eventually disable in Windows 11.

This NTLM traffic bug is in addition to VPN connection issues that currently also affect Windows Server systems, alongside Windows 10 and 11.

As always, the bug was posted on the Windows Health Dashboard site, Microsoft’s name Author:

After installing the April 2024 security update (KB5036909) on domain controllers (DCs), you may notice a significant increase in NTLM authentication traffic. This issue may affect organizations that have a very small percentage of PDCs in their environment and high NTLM traffic.

next steps: We are working on a solution and will provide an update in the next release.

Windows support:

Enterprise Devices: Get help for your organization with Business Support.

Affected platforms:

Customer: None

Server: Windows Server 2022, Windows Server 2019, Windows Server 2016, Windows Server 2012 R2, Windows Server 2012, Windows Server 2008 R2, Windows Server 2008

So, like the VPN bug and broken profile pictures, Microsoft says a future update will fix the NTLM issue.