How to fix Error 11549 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: Error 11549 in SQL Server 2025

Why This Error Happens

Error 11549 occurs when the sp_showmemo_xml stored procedure receives an input parameter type that references a deprecated or unsupported memo/text-based object, which SQL Server 2025 no longer processes through standard procedure calls. This typically happens because the input parameter points to a legacy data type (such as ntext or image) rather than the expected varchar(max), nvarchar(max), or xml type. It can also surface when the procedure is invoked against a linked server or compatibility-level database that hasn’t been updated to align with SQL Server 2025’s engine requirements.

Step-by-Step Resolution Guide

Step 1: Verify the Input Parameter Data Type

  • Open SQL Server Management Studio (SSMS) and locate the calling script or application code that invokes sp_showmemo_xml.
  • Check the parameter being passed; it must not be ntext, text, or image — these are deprecated.
  • Run the following to inspect the parameter type:
EXEC sp_help 'sp_showmemo_xml';
  • Confirm the parameter definitions match current large-object (LOB) types.

Step 2: Convert the Parameter to a Supported Type

  • Modify the calling code to explicitly cast the input to varchar(max) or xml before passing it to the procedure.
  • Example fix:
DECLARE @InputData XML = CAST(@OriginalMemoField AS XML);
EXEC sp_showmemo_xml @InputData;
  • Avoid implicit conversions, as SQL Server 2025 strictly validates parameter types for this procedure.

Step 3: Check Database Compatibility Level

  • Navigate to Databases > [Your Database] > Properties > Options in SSMS.
  • Confirm the Compatibility Level is set to SQL Server 2025 (160) or higher.
  • If it’s set lower, update it using:
ALTER DATABASE [YourDatabaseName] SET COMPATIBILITY_LEVEL = 160;
  • Restart the SQL Server service via Services.msc on Windows Server 2025 if the setting doesn’t apply immediately.

Step 4: Update or Recompile the Stored Procedure

  • If a custom version of sp_showmemo_xml exists in your database (rather than the system-provided one), drop and recreate it using updated syntax that supports xml and varchar(max) types.
  • Use sp_recompile to force SQL Server to regenerate the execution plan:
EXEC sp_recompile 'sp_showmemo_xml';

Alternative or Verification Steps

  • Verify the fix: Re-run the original query or application call that triggered Error 11549. If no error appears and the XML/memo data displays correctly, the issue is resolved.
  • Alternative solution: If the error persists, bypass the procedure entirely and query the underlying table directly using CAST/CONVERT functions to retrieve the memo field as XML, then validate the output structure manually before reintroducing the stored procedure call.