Microsoft has released out-of-band (OOB) updates today, April 19, 2026, to address issues introduced by the April 2026 Windows security update.
A limited number of Windows Server 2025 devices might experience failures installing the April 2026 security update (
KB5082063). In addition, some versions of Windows Server may experience
domain controllers restarting repeatedly after installing the April 2026 security update.
To address these issues, Microsoft has released OOB updates for the Windows Server versions listed below. Note: The Windows Server 2025 OOB update (
KB5091157) addresses both the installation failure issue and the domain controller restart issue. OOB updates released for other supported Windows Server versions address only the domain controller restart issue.
For complete guidance and installation instructions, see the relevant KB articles:
Standard Windows updates
Windows hotpatch updates