How to fix Error 6562 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: SQL Server Error 6562 – File Version Mismatch

Why This Error Happens

Error 6562 occurs when SQL Server 2025 detects that internal binary files (such as DLLs, resource files, or extended stored procedure libraries) do not share the same build version, typically because a patch, cumulative update, or hotfix was only partially applied. This mismatch can also result from a corrupted installation, an interrupted Windows Update that overwrote shared system files, or manual copying of SQL Server binaries between servers running different versions. Since SQL Server strictly validates internal component versioning at startup or during specific operations, even a minor discrepancy between two interdependent files will trigger this error and may prevent the service or feature from loading correctly.

Step-by-Step Resolution Guide

Step 1: Identify the Exact Files and Versions in Conflict

  • Open the SQL Server Error Log located at C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Log\ERRORLOG (adjust instance folder name as needed for SQL Server 2025).
  • Locate the full error string: Version mismatch between files '%ls' (%d.%d.%d) and '%ls' (%d.%d.%d) to note the two specific file paths and their version numbers.
  • Cross-reference both file versions against the official build number for your currently installed Cumulative Update (CU) on the Microsoft SQL Server release notes page.

Step 2: Verify and Repair the SQL Server Installation

  • Open Control Panel > Programs and Features, select Microsoft SQL Server 2025, and click Uninstall/Change.
  • Choose Repair from the SQL Server Installation Center wizard to force all core binaries back to a consistent baseline version.
  • Alternatively, run the setup executable directly from an elevated Command Prompt:
  setup.exe /ACTION=Repair /INSTANCENAME=MSSQLSERVER /QUIET

Step 3: Reapply the Latest Cumulative Update (CU) Consistently

  • Download the latest SQL Server 2025 Cumulative Update package directly from the Microsoft Update Catalog (avoid mixing CUs from different sources).
  • Run the CU installer as Administrator and ensure it completes fully without interruption; do not reboot or cancel mid-installation.
  • Confirm all instance features (Database Engine, Analysis Services, Integration Services) are updated together, since partial component updates are the most common cause of this mismatch.

Step 4: Check for File-Level Corruption or Permission Blocks

  • Navigate to the Binn folder (e.g., C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Binn) and verify that antivirus or EDR software has not quarantined or locked any .dll files.
  • Run sfc /scannow in an elevated Command Prompt on Windows Server 2025 / Windows 11 to repair any corrupted shared system libraries that SQL Server depends on.
  • Restart the SQL Server service via services.msc or net start MSSQLSERVER after confirming file integrity.

Alternative or Verification Steps

  • After applying the repair and CU, restart the SQL Server service and check the ERRORLOG again to confirm Error 6562 no longer appears during startup.
  • If the error persists, consider a clean uninstall followed by a fresh installation of SQL Server 2025 plus the latest CU in a single pass, rather than incremental patching, to guarantee all binaries match the same build version.