How To Fix OL401 - Enter the name of a function module parameter

SAP Error Message - Details

• Message type: E = Error

• Message class: OL - Workflow object types: Run-time system

• Message number: 401

• Message text: Enter the name of a function module parameter

What causes this issue?

For BAPI methods, each method parameter must correspond to a parameter
of the corresponding function module.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Enter the name of the corresponding parameter of the function module.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message OL401 - Enter the name of a function module parameter ?

  The SAP error message OL401, which states "Enter the name of a function module parameter," typically occurs when you are working with function modules in the ABAP environment and you have not provided a required parameter name in a function module call or definition.
  Cause:
  
  Missing Parameter Name: The error usually arises when you are trying to call a function module, but you have not specified the name of one of its parameters.
  Incorrect Syntax: There may be a syntax error in the way the function module is being called or defined.
  Parameter Not Defined: The function module you are trying to use may have parameters that are mandatory, and you have not provided values for them.
  
  Solution:
  
  Check Function Module Definition: Go to transaction SE37 (Function Builder) and check the definition of the function module you are trying to use. Ensure that you are aware of all the parameters it requires.
  Provide Parameter Names: When calling the function module, make sure to specify all required parameters correctly. For example:
  CALL FUNCTION 'FUNCTION_MODULE_NAME'
    EXPORTING
      PARAMETER_NAME = value
    IMPORTING
      RETURN_PARAMETER = return_value.
  
  Review Syntax: Ensure that your ABAP code syntax is correct. Look for any typos or missing components in your function call.
  Use the Correct Data Types: Ensure that the values you are passing to the parameters match the expected data types defined in the function module.
  
  Related Information:
  
  Transaction SE37: Use this transaction to view and edit function modules.
  Function Module Documentation: Each function module has documentation that describes its parameters, expected input, and output. This can be accessed in SE37.
  ABAP Debugger: If you are still having trouble, you can use the ABAP debugger to step through your code and see where the error occurs.
  SAP Notes: Check SAP Notes for any known issues or updates related to the specific function module you are using.
  
  By following these steps, you should be able to resolve the OL401 error and successfully call the function module with the required parameters.