Microsoft has warned IT administrators about a critical issue affecting Windows Server 2025 domain controllers. Following a system restart, these servers may fail to manage network traffic correctly, potentially causing disruptions in Active Directory (AD) environments.

This problem arises because the domain controllers load the standard firewall profile instead of the required domain firewall profile after rebooting.

The misapplied firewall profile leads to several issues:

Domain controllers may become inaccessible on the domain network.
Applications and services running on affected servers or remote devices may fail or remain unreachable.
Ports and protocols that should be restricted by the domain firewall profile may remain open, posing potential security risks1 3.

This issue affects only Windows Server 2025 systems hosting the Active Directory Domain Services role. No client systems or earlier server versions are impacted.

Workaround for Affected Systems

Microsoft has provided a temporary workaround to mitigate the issue. Administrators can manually restart the network adapter on affected servers using PowerShell with the following command:

textRestart-NetAdapter *

However, this workaround must be applied after every system restart, as the problem reoccurs each time the server reboots.

To streamline this process, Microsoft recommends creating a scheduled task that automatically restarts the network adapter whenever the domain controller restarts.

The issue stems from domain controllers failing to apply the correct network profile after a reboot. Instead of loading the “Domain Authenticated” profile, they default to a “Public” or standard firewall profile. This behavior disrupts essential AD functions such as Group Policy application, replication, and authentication.

Similar issues were observed in previous versions like Windows Server 2022, but prior fixes do not resolve this problem in Windows Server 2025.

Microsoft has confirmed that its engineers are actively working on a permanent resolution. A fix is expected to be included in an upcoming update, though no specific timeline has been provided.

Recommendations for Administrators

Until a permanent fix is released, administrators are advised to:

Implement the manual workaround or automate it using scheduled tasks.
Monitor their domain controllers closely for connectivity and service disruptions.
Avoid unnecessary restarts of affected servers whenever possible.

Affected organizations should prepare for potential downtime during restarts and ensure that critical services relying on Active Directory remain operational through these temporary measures.

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