How to fix Error 13111 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: SQL Server Error 13111 — Generic Waitable Object

Why This Error Happens

Error 13111 in SQL Server 2025 is typically raised when the SQLOS scheduler encounters a synchronization timeout on an internal waitable object, often triggered by resource contention or a corrupted internal handle table. This condition commonly surfaces after abrupt service terminations, insufficient worker thread availability, or when third-party security software intercepts SQL Server’s internal thread signaling mechanisms. In most cases, it is not caused by data corruption itself, but by the operating system failing to release handles that SQL Server’s Service Broker or availability group components depend on.

Step-by-Step Resolution Guide

Step 1: Verify SQL Server Service Account Permissions

  • Open Services.msc on Windows Server 2025 / Windows 11 and confirm the SQL Server service is running under the correct domain or virtual account.
  • Ensure the account has the “Lock pages in memory” and “Perform volume maintenance tasks” policies assigned via secpol.msc.
  • Restart the service after any permission change: net stop MSSQLSERVER && net start MSSQLSERVER.

Step 2: Clear Orphaned Handles and Restart SQLOS Scheduler

  • Open SQL Server Configuration Manager and check the SQL Server Network Configuration for stalled TCP/IP listener threads.
  • Run the following query to identify blocked waitable objects:
    SELECT * FROM sys.dm_os_wait_stats WHERE wait_type LIKE '%GENERIC%';
  • If orphaned sessions are found, terminate them using KILL <session_id>;.

Step 3: Check for Antivirus or EDR Interference

  • Exclude the SQL Server data, log, and tempdb directories (e.g., C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\DATA) from real-time scanning.
  • Temporarily disable Windows Defender Exploit Protection for sqlservr.exe to test if the handle release issue resolves.

Step 4: Apply the Latest Cumulative Update

  • Navigate to the Microsoft Update Catalog and download the latest CU for SQL Server 2025.
  • Install the patch in single-user mode if the error persists during peak transaction load: sqlservr.exe -m -T4022.

Alternative or Verification Steps

  • Verify the fix by monitoring the SQL Server Error Log (ERRORLOG file in the MSSQL\Log directory) for 24 hours to confirm Error 13111 no longer appears during high-concurrency transactions.
  • If the error persists, run DBCC CHECKDB with the DATA_PURITY option to rule out underlying page-level corruption as an alternative root cause.