How to fix Error 7802 on Windows Server 2025 / Windows 11

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Why This Error Happens

Error 7802 occurs when a SOAP/HTTP endpoint attempts to expose a stored procedure or user-defined function whose return type cannot be serialized into a valid SOAP/XML response. This typically happens with return types such as cursor, table, sql_variant, or CLR user-defined types, which have no direct WSDL/XSD mapping. The issue is a metadata/configuration mismatch at the endpoint definition level rather than a corruption or permissions problem — SQL Server’s native HTTP SOAP layer simply refuses to publish an incompatible signature.

Step-by-Step Resolution Guide

Step 1: Identify the Offending Function or Procedure

  • Run SELECT * FROM sys.endpoints WHERE type_desc = 'SOAP' to list active HTTP SOAP endpoints.
  • Cross-reference with sys.endpoint_webmethods to find which stored procedure/function is mapped to the endpoint throwing 7802.
  • Check the return type of that routine using sp_help '<SchemaName.ObjectName>'.

Step 2: Modify the Return Type or Wrapper Logic

  • Rewrite the function/procedure to return a supported scalar type (int, varchar, nvarchar, bit, datetime, etc.) instead of cursor, table, or sql_variant.
  • If a result set is required, convert the output to a well-formed XML document using FOR XML PATH or FOR XML AUTO and return it as xml or nvarchar(max).
  • Example fix:
  ALTER PROCEDURE dbo.GetCustomerData
  AS
  BEGIN
      SELECT * FROM Customers FOR XML AUTO, ELEMENTS
  END

Step 3: Recreate or Alter the SOAP Endpoint

  • Drop and recreate the endpoint pointing to the corrected routine:
  DROP ENDPOINT CustomerSoapEndpoint;
  CREATE ENDPOINT CustomerSoapEndpoint
      STATE = STARTED
      AS HTTP (PATH = '/sql/customerdata', AUTHENTICATION = (INTEGRATED), PORTS = (CLEAR))
      FOR SOAP (
          WEBMETHOD 'GetCustomerData' (NAME = 'dbo.GetCustomerData'),
          WSDL = DEFAULT
      );
  • Confirm there are no port conflicts on 80/443 using netstat -ano | findstr :80 in an elevated PowerShell session on Windows Server 2025.

Step 4: Restart the SQL Server Service

  • Restart via services.msc or Restart-Service -Name MSSQLSERVER (or the named instance service) to force the HTTP.sys listener to reload endpoint metadata.
  • Confirm the SQL Server error log no longer logs Error 7802 on startup.

Alternative or Verification Steps

  • Test the endpoint using a SOAP client (e.g., Invoke-WebRequest or SoapUI) and confirm the WSDL generates correctly at http://<server>/sql/customerdata?wsdl without errors.
  • If native SOAP support continues to fail, consider migrating the function to a REST-based wrapper (e.g., via SQL Server’s native JSON/HTTP services or a middle-tier API), since Microsoft recommends REST endpoints over legacy SOAP for new development in SQL Server 2025.