[German]The cumulative updates released on April 14, 2026, for Windows Server 2016 through Windows Server 2025 (e.g., KB508206 for Windows Server 2025) cause domain controllers to reboot under certain conditions. I got some reports from my German blog readers during the last hours.
Following user reports, Microsoft has since confirmed this issue as a known issue in the Windows Release Health Dashboard for Windows Server 2025, etc. More details may be read at my German blog post [use the build-in translator to switch language].
Thanks for flagging this so quickly. We saw the same reports from clients running Server 2016 on their domain controllers after the April 14 updates.
Ironically, this kind of disruptive patch behaviour is exactly what makes the January 2027 EOL deadline feel more urgent. Once support ends, there's no Microsoft response when something like this happens — no hotfix, no health dashboard update, nothing. Organisations that are already finding patch management painful on Server 2016 are probably better off using the remaining time to plan a migration rather than holding on.
We put together a guide specifically for businesses weighing up their options before the deadline: https://www.oceantele.com/windows-server-2016-end-of-life/ — covers ESUs as a short-term bridge if migration isn't possible in time.