Microsoft releases emergency updates to fix Windows Server issues

by · BleepingComputer

Microsoft has released out-of-band (OOB) updates to fix issues affecting Windows Server systems after installing the April 2026 security updates.

As Microsoft confirmed last week, some admins may experience failures when installing the KB5082063 security update on Windows Server 2025 devices.

Additionally, this month's Patch Tuesday cumulative updates are causing some Windows servers with domain controller roles to enter a restart loop due to crashes of the Local Security Authority Subsystem Service (LSASS).

Microsoft also warned that this issue may also occur when setting up new domain controllers (or even on existing ones) if the server processes authentication requests very early during startup.

To address these two known issues, Microsoft has released emergency updates for the following affected Windows Server versions:

"The Windows Server 2025 OOB update (KB5091157) addresses both the installation failure issue and the domain controller restart issue," Microsoft explained. "OOB updates released for other supported Windows Server versions address only the domain controller restart issue."

On Wednesday, Microsoft also warned admins that some Windows Server 2025 devices will boot into BitLocker recovery and prompt users to enter a BitLocker key after installing the KB5082063 Windows security update.

Additionally, last week, it finally addressed a bug that has been plaguing Windows servers since September 2024, causing devices running Windows Server 2019 and Windows Server 2022 to upgrade to Windows Server 2025 "unexpectedly."

Since the start of the year, Microsoft has also released emergency updates to resolve a Bluetooth device visibility bug and patch security vulnerabilities in the Routing and Remote Access Service (RRAS) management tool that affect hotpatch-enabled Windows 11 Enterprise devices.

Two other sets of out-of-band updates addressed broken sign-ins with Microsoft accounts and update installation issues affecting the March 2026 non-security preview update.

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