Microsoft has issued a warning to IT administrators regarding potential connectivity issues with Windows Server 2025 domain controllers (DCs). Following a restart, these servers may fail to manage network traffic appropriately, which can result in applications and services being unreachable on the domain network.
According to a recent update on the Windows release health dashboard, after a reboot, the affected domain controllers revert to using the standard firewall profile instead of the domain firewall profile. This malfunction can lead to poor management of network traffic, allowing access over unauthorized ports and protocols, which should typically be blocked. Consequently, services running on those domain controllers or devices connected to the domain can become inaccessible or completely fail.
As a temporary measure, administrators are advised to manually restart the network adapter each time the server is rebooted. This can be achieved using the PowerShell command Restart-NetAdapter. Microsoft also recommends creating a scheduled task to automate this process at every server startup.
Currently, there is no patch available to resolve the issue, but Microsoft is actively working on a fix that will be provided in a future update.
For further details, users can refer to the Windows release health dashboard.