Microsoft warns Windows Server 2025 changes may cause app crashes

Microsoft warned customers last week that some applications on Windows Server 2025 may crash because of recent memory-management changes.

The known issue affects applications that use Address Windowing Extensions (AWE), which allow an application to use more than 4GB of physical memory within a 32-bit virtual address space.

Microsoft said affected applications may encounter access violations, memory corruption, or unexpected termination. The issue can affect SQL Server when the Lock Pages in Memory (LPIM) Windows policy is enabled. Reported symptoms include memory corruption errors, access-violation exceptions with 0xC0000005 error codes, failures during database maintenance operations such as DBCC CHECKDB, SQL Server crash dumps, and services stopping or restarting unexpectedly. Some users may also see “Using locked pages in the memory manager.” alerts during system startup.

A permanent fix is not available yet. Microsoft’s temporary workaround requires administrators to disable LPIM for the SQL Server service account, but the company said this can affect SQL Server performance and memory-management behavior. For other affected applications, Microsoft advised checking whether AWE can be disabled.

Microsoft said it is working on a resolution for a future Windows update. In April 2026, it also released emergency updates for a Windows Server 2025 issue that prevented the KB5082063 security update from installing on some systems.