How to fix Error 4150 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: SQL Server Error 4150 — Hints Not Allowed on Recursive CTE References

Why This Error Happens

This error occurs because SQL Server’s query optimizer does not permit table hints (such as NOLOCK, INDEX, or FORCESEEK) to be applied directly to the recursive member reference inside a Common Table Expression (CTE). The recursive invocation of the CTE is treated as a self-referencing virtual table rather than a physical table, so the engine cannot resolve physical access hints against it. This typically surfaces after a code migration, a copy-pasted query template, or an ORM-generated script that appends default hints to every table reference without distinguishing recursive CTE calls.

Step-by-Step Resolution Guide

Step 1: Identify the Offending Query

  • Open the query indicated in the error message (visible in SSMS, Query Store, or the application’s exception log).
  • Locate the WITH cte_name AS (...) block and find the recursive anchor/recursive member section.
  • Search specifically for hint syntax like WITH (NOLOCK), WITH (INDEX(...)), or WITH (FORCESEEK) attached to the recursive self-reference (the part of the UNION ALL that calls the CTE itself).

Step 2: Remove the Hint from the Recursive Reference

  • Edit the T-SQL script and strip out the hint clause only from the recursive member’s reference to the CTE (not necessarily the anchor member, which may still reference a base table with a hint).
  • Example fix:
  • Incorrect: SELECT * FROM cte_name WITH (NOLOCK) WHERE ...
  • Corrected: SELECT * FROM cte_name WHERE ...
  • Save the corrected script and redeploy it to the relevant stored procedure, view, or function using SSMS or your deployment pipeline (e.g., Azure DevOps, SSDT project).

Step 3: Audit for Template-Generated Hints

  • If the query was generated by an ORM (Entity Framework, Dapper) or a code generator, check the template or interceptor responsible for injecting hints globally.
  • Update the generation logic to exclude CTE recursive blocks, or add a post-processing regex step to strip hints from WITH ... AS (...) recursive sections before execution.
  • Re-run the generated SQL in SSMS to confirm Error 4150 no longer appears.

Step 4: Validate Query Logic Without the Hint

  • Since hints like NOLOCK were likely used for performance tuning, re-evaluate whether the recursive CTE needs alternative tuning.
  • Consider using OPTION (MAXRECURSION n) at the end of the outer query instead, which is supported and does not trigger Error 4150.
  • Test execution plans using SET STATISTICS IO, TIME ON to ensure performance remains acceptable after hint removal.

Alternative or Verification Steps

  • Run the corrected query directly in SSMS or Azure Data Studio connected to your SQL Server 2025 instance; confirm it executes without raising Error 4150 and returns expected recursive results.
  • If hints are required for performance reasons, move them to the anchor member or to the outer SELECT statement wrapping the CTE invocation instead of the recursive self-reference, and validate via SET SHOWPLAN_XML ON that the hint is applied correctly without errors.