How to fix Error 9935 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: Error 9935 – “Warning: Wordbreaker”

Why This Error Happens

Error 9935 occurs when SQL Server’s Full-Text Search engine encounters a mismatch or corruption in the wordbreaker/filter component registered for a specific language LCID. This typically happens after a Windows Update, OS migration, or SQL Server upgrade that fails to properly re-register the sqlserver.xml configuration or the associated wordbreaker DLL files (e.g., MSFTEWBK.dll). Additionally, missing read/execute permissions on the Full-Text binaries folder for the SQL Server service account can prevent the engine from loading the component correctly.

Step-by-Step Resolution Guide

Step 1: Verify the Wordbreaker Registration in sqlserver.xml

  • Navigate to the Full-Text binaries directory, typically located at C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Binn\FTData\sqlserver.xml.
  • Open the XML file and locate the <Language> tag matching the LCID referenced in the error log (check SQL Server Error Log for the specific LCID number).
  • Ensure the Wordbreaker_DLL and Stemmer_DLL paths point to valid, existing files (e.g., MSFTEWBK.dll) and are not pointing to a deprecated path from a previous OS/SQL version.

Step 2: Reset Permissions on the FTData Directory

  • Open File Explorer and navigate to C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Binn\FTData.
  • Right-click the folder, select Properties > Security, and ensure the SQL Server service account (e.g., NT Service\MSSQLSERVER) has Read & Execute permissions.
  • If permissions are missing, click Edit, add the service account, and apply Read & Execute access to this folder, subfolders, and files.

Step 3: Re-run the Full-Text Configuration Repair

  • Open SQL Server Configuration Manager and stop the SQL Server (MSSQLSERVER) and SQL Server Full-Text Daemon Launcher (MSSQLSERVER) services.
  • Launch an elevated Command Prompt and run the repair utility to force re-registration of the wordbreaker components:
  setup.exe /ACTION=REPAIR /INSTANCENAME=MSSQLSERVER /FTREBUILD=True
  • Restart both services via Configuration Manager once the repair process completes.

Step 4: Rebuild the Affected Full-Text Index

  • Connect to the instance via SQL Server Management Studio (SSMS).
  • Execute the following T-SQL command against the specific database to force the engine to reload the wordbreaker rules:
  ALTER FULLTEXT INDEX ON [YourTableName] REBUILD;
  • Check the SQL Server Error Log immediately after the rebuild to confirm Error 9935 does not reappear.

Alternative or Verification Steps

  • Verification: Run SELECT * FROM sys.dm_fts_parser('"test string"', LCID, 0, 0); in SSMS to confirm the specific LCID parses text without throwing an exception.
  • Alternative: If the error persists, uninstall and reinstall the Full-Text and Semantic Extractions for Search feature via the SQL Server Installation Center to force a clean overwrite of all wordbreaker binaries.