Updates for Windows Server 2025
Windows Server 2025 is the latest release in our Long Term Servicing Channel. On the left side of this page, you’ll find a list of all the updates released for this version of Windows Server. You can also find more information about releases and any known issues. Installing the most recent update ensures that you also get any previous updates you might have missed, including any important security fixes.
Current status of Windows Server 2025
For the most up-to-date information about known issues for Windows and Windows Server, please go to the Windows release health dashboard.
Known issues
Apps using Address Windowing Extensions might experience access violations
Symptoms
Applications running on Windows Server 2025 might experience access violations, memory corruption, or unexpected termination. This issue is caused by a Windows Server 2025 memory-management change that can affect certain applications using Address Windowing Extensions (AWE) that rely on memory-management behaviors present in earlier Windows Server releases.
Known affected applications include SQL Server running with Lock Pages in Memory (LPIM) enabled. Reported symptoms include:
Access violation exceptions (0xC0000005/EXCEPTION_ACCESS_VIOLATION)
Memory corruption errors
SQL Server crash dumps
SQL Server services unexpectedly stopping or restarting
Failures during database maintenance operations such as DBCC CHECKDB
Workaround
Affected customers can apply one of the following workarounds to mitigate the issue:
1. Disable LPIM for affected SQL Server instances
For SQL Server, a temporary workaround is available. Administrators can disable the LPIM configuration for affected SQL Server instances to prevent utilization of AWE. Customers should evaluate this workaround in their environment, as disabling LPIM can affect SQL Server performance and memory-management behavior. For detailed guidance review the release notes applicable to your SQL server version:
For other applications encountering this issue, check to see if AWE can be disabled.
2. Mitigate through Known Issue Rollback (KIR): This issue is mitigated using Known Issue Rollback (KIR).
For enterprise-managed devices where Windows updates are managed by IT departments, IT administrators can apply the KIR by installing and configuring the Group policy listed below. The special Group Policy can be found in Computer Configuration > Administrative Templates > <Group Policy name listed below>.
Group Policy downloads with Group Policy name:
- Download for Windows Server 2025: Windows Server 2025 KB5126646 260911_030215 Known Issue Rollback
Important: You will need to install and configure the Group Policy for your version of Windows to resolve this issue. You will also need to restart your device(s) to apply the group policy setting. Note that this Group Policy will disable the change causing this issue until a resolution is released in a future Windows update.
For information on deploying and configuring this special Group Policy, see Use Group Policy to enable an update that is disabled by default.
Microsoft is working on a resolution for this issue in a future Windows update and will provide more information when it is available.
Notes and messages
None.