How to fix Error 1075 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: SQL Server Error 1075 — “RETURN Statements in Scalar Valued Functions Must Include an Argument”

Why This Error Happens

This error occurs because SQL Server’s T-SQL syntax rules require every scalar-valued function (SVF) to explicitly return a value of the declared return type via the RETURN statement. This is a compile-time parsing error (Error 1075), not a permissions or connectivity issue — it is triggered when a developer writes RETURN; with no expression, or omits the RETURN statement entirely on a code path inside a CREATE FUNCTION / ALTER FUNCTION block. Because scalar functions must always produce a single typed value, the SQL Server 2025 query parser rejects the object creation/compilation before it is ever registered in the database engine.

Step-by-Step Resolution Guide

Step 1: Identify the Offending Function Definition

  • Open SQL Server Management Studio (SSMS) or Azure Data Studio connected to your Windows Server 2025 / Windows 11 instance.
  • Locate the exact CREATE FUNCTION or ALTER FUNCTION script that failed — the error message in the Messages pane will reference the line number of the bad RETURN statement.
  • Run SELECT definition FROM sys.sql_modules WHERE object_id = OBJECT_ID('YourFunctionName'); if the function partially exists and you need to inspect it.

Step 2: Correct the RETURN Statement Syntax

  • Edit the function body so every RETURN includes a value matching the declared RETURNS data type, e.g.:
  CREATE FUNCTION dbo.GetTotal (@OrderId INT)
  RETURNS DECIMAL(10,2)
  AS
  BEGIN
      DECLARE @Total DECIMAL(10,2);
      SELECT @Total = SUM(LineTotal) FROM OrderDetails WHERE OrderId = @OrderId;
      RETURN ISNULL(@Total, 0);  -- must return a value, not just RETURN;
  END
  • Check all branching logic (IF, WHILE, CASE) to ensure there is no code path that hits a bare RETURN; or falls through without hitting any RETURN at all.

Step 3: Re-Deploy and Validate the Script

  • Drop and recreate the function using DROP FUNCTION IF EXISTS dbo.YourFunctionName; followed by the corrected CREATE FUNCTION statement.
  • Execute the script in a new query window to confirm it compiles with zero errors (Command completed successfully).
  • If deploying via a DACPAC/SSDT project in Visual Studio on Windows 11, rebuild the project first to catch the same error locally before publishing to the SQL Server 2025 instance.

Step 4: Audit Related Functions for the Same Pattern

  • Run a metadata search across the database to catch similar issues proactively:
  SELECT o.name, m.definition
  FROM sys.sql_modules m
  JOIN sys.objects o ON m.object_id = o.object_id
  WHERE o.type = 'FN' AND m.definition LIKE '%RETURN;%';
  • Fix any additional functions flagged by this query using the same method as Step 2.

Alternative or Verification Steps

  • Verify the fix by executing the function directly, e.g., SELECT dbo.GetTotal(1001); — a successful result set with no red error text confirms the function compiled and executes correctly.
  • If the function logic genuinely has no meaningful value to return on certain paths, use a multi-statement table-valued function (RETURNS @ReturnTable TABLE (...)) instead of a scalar function, since table-valued functions do not require a typed RETURN expression.