How to fix Error 10715 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: SQL Server Error 10715 – ‘Is Not a Valid Hint’

Why This Error Happens

Error 10715 occurs when SQL Server’s query parser encounters a hint in a query (within an OPTION clause, WITH clause, or OPTIMIZE FOR statement) that it does not recognize as a valid, supported keyword. This is typically caused by a typo in the hint name, the use of a deprecated hint that has been removed in SQL Server 2025, or application code written for a different database platform (or an older/newer T-SQL dialect) that uses incompatible syntax. It can also surface after a Compatibility Level change, where hints valid in older modes are no longer parsed the same way.

Step-by-Step Resolution Guide

Step 1: Identify the Exact Offending Query

  • Capture the exact T-SQL statement throwing error 10715 using SQL Server Profiler, Extended Events, or by reviewing the application’s error logs.
  • Look for the specific hint string referenced in the error message (e.g., OPTION (HASH JOIN) vs. an invalid variant like OPTION (HASHJOIN)).
  • Check C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Log\ERRORLOG for the full query context if captured.

Step 2: Validate Hint Syntax Against Supported Keywords

  • Cross-reference the hint against the official Microsoft documentation for supported Query, Table, and Join hints in SQL Server 2025.
  • Correct common mistakes such as missing parentheses, extra commas, or hints merged together without spaces.
  • Example of a corrected syntax:
  SELECT * FROM Orders WITH (NOLOCK) OPTION (RECOMPILE);

Step 3: Check for Deprecated or Removed Hints

  • Review the “Deprecated Database Engine Features” documentation for SQL Server 2025, as some legacy hints (common in SQL Server 2012–2016 era code) may have been fully removed in this release.
  • If a legacy hint is found, replace it with its modern equivalent or remove it if it no longer serves a purpose under the current Query Optimizer.
  • Update any ORM frameworks (like Entity Framework or Dapper) or stored procedures that may be auto-generating the invalid hint string.

Step 4: Verify Database Compatibility Level

  • Open SQL Server Management Studio (SSMS) and run the following command to check the current compatibility level:
  SELECT name, compatibility_level FROM sys.databases WHERE name = 'YourDatabaseName';
  • If the hint relies on behavior from a specific compatibility mode, ensure the database is set to the correct level (e.g., 170 for SQL Server 2025) using:
  ALTER DATABASE YourDatabaseName SET COMPATIBILITY_LEVEL = 170;

Alternative or Verification Steps

  • Verification: Re-run the corrected query in a new SSMS query window connected to the Windows Server 2025 instance; confirm the query executes successfully and returns the expected execution plan without triggering Error 10715.
  • Alternative: If the hint is syntactically correct but still fails, temporarily remove the hint entirely to confirm the query runs, then consult the Microsoft Q&A forums or Azure Data Studio’s IntelliSense validation to confirm the hint is supported in the 2025 engine build you are running.