How to fix Error 4606 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: SQL Server Error 4606

Why This Error Happens

Error 4606 occurs when a GRANT, DENY, or REVOKE statement attempts to apply a privilege type that is not valid for the target object’s class. This typically happens when permissions designed for one securable (such as a database-level permission like CREATE TABLE) are mistakenly applied to an incompatible object (such as a scalar function, view, or system object that doesn’t support that specific action). It can also surface after an in-place upgrade to SQL Server 2025 where deprecated permission mappings from older compatibility levels no longer align with the updated metadata schema.

Step-by-Step Resolution Guide

Step 1: Identify the Exact Statement and Object Class

  • Capture the full T-SQL script that triggered the error from the SQL Server Error Log located at C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Log\ERRORLOG.
  • Run SELECT * FROM sys.fn_builtin_permissions(DEFAULT); to cross-reference whether the specific privilege (e.g., ALTER, CONTROL, VIEW DEFINITION) is actually supported by the object class you are targeting (e.g., OBJECT, SCHEMA, DATABASE).
  • Note the exact securable_class returned in the query results.

Step 2: Correct the Permission Scope in the Script

  • Modify the T-SQL syntax to target the correct scope. For example, if you tried to run GRANT SELECT ON FUNCTION::myFunc TO user1 but the function is a scalar type that doesn’t support column-level results, switch to GRANT EXECUTE instead.
  • Use the OBJECT:: prefix explicitly to ensure the engine isn’t defaulting to a broader SCHEMA or DATABASE scope, for example: GRANT ALTER ON OBJECT::dbo.MyTable TO [DOMAIN\User];

Step 3: Validate Compatibility Level Settings

  • Check the database compatibility level, as SQL Server 2025 defaults to 170, which may restrict legacy permission grants used in older compatibility levels (like 100 or 110).
  • Run the following command to verify the current setting:
  • SELECT name, compatibility_level FROM sys.databases WHERE name = 'YourDBName';
  • If necessary, update it to align with 2025 standards: ALTER DATABASE YourDBName SET COMPATIBILITY_LEVEL = 170;

Step 4: Clear and Rebuild the Permission Set

  • If the object’s permission metadata appears corrupted after a migration, drop the existing permission set entirely using REVOKE ALL PRIVILEGES ON OBJECT::dbo.MyTable FROM [DOMAIN\User];.
  • Restart the SQL Server service via services.msc or by running net stop MSSQLSERVER && net start MSSQLSERVER in an elevated Command Prompt to clear the permission cache.
  • Re-apply the specific, compatible grant statement identified in Step 1.

Alternative or Verification Steps

  • Verify the fix by querying sys.database_permissions joined with sys.objects to confirm the permission_name matches the type_desc of the target object without throwing a red execution error.
  • If the error persists, use SQL Server Management Studio (SSMS) 21’s GUI-based permission explorer (right-click Object > Properties > Permissions) instead of raw T-SQL, as the GUI automatically filters out incompatible permission options for the selected object type.