How To Fix FQ798 - Inadmissable field change in user exit &

SAP Error Message - Details

• Message type: E = Error

• Message class: FQ - Payment Requests and Payment Program

• Message number: 798

• Message text: Inadmissable field change in user exit &

What causes this issue?

In the Userexit &V1& a document header field was changed, that does not
belong to the SAP Standards field. These fields must not be changed in
the Userexit.

System Response

Further processing is not possible.

How to fix this error?

Please check the Usersexits characteristic &V1&

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message FQ798 - Inadmissable field change in user exit & ?

  The SAP error message FQ798, which states "Inadmissible field change in user exit &," typically occurs in the context of financial transactions, particularly when there are inconsistencies or unauthorized changes being made to fields that are not allowed to be modified during certain processes. This error is often related to user exits or enhancements that are implemented in the SAP system.
  Cause:
  
  Field Modification: The error usually arises when a user exit or enhancement attempts to change a field that is not permitted to be modified at that point in the transaction process. This can happen if the field is part of a validation or if it is locked during certain processing stages.
  Incorrect Logic in User Exit: If the logic implemented in the user exit is not aligned with the standard SAP processing rules, it can lead to this error.
  Data Consistency Issues: The system may detect that changing the field would lead to data inconsistencies, especially in financial documents.
  
  Solution:
  
  Review User Exit Logic: Check the code in the user exit that is causing the error. Ensure that it does not attempt to modify fields that are restricted during the transaction.
  Debugging: Use the SAP debugger to trace the execution of the user exit and identify the exact point where the error occurs. This can help in understanding which field is being modified and why it is causing the error.
  Consult Documentation: Refer to SAP documentation or notes related to the specific user exit being used. There may be guidelines on which fields can be modified and under what conditions.
  Adjust User Exit: If necessary, modify the user exit code to ensure that it adheres to the rules of the transaction. This may involve adding checks to prevent changes to certain fields.
  Testing: After making changes, thoroughly test the transaction to ensure that the error no longer occurs and that the business process functions as expected.
  
  Related Information:
  
  User Exits: User exits are predefined points in the SAP standard code where custom code can be added. They are often used to enhance functionality without modifying the standard SAP code.
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional guidance on handling user exits.
  Transaction Codes: Familiarize yourself with transaction codes related to the financial processes you are working with, as they may provide insights into where the error is occurring.
  
  If the issue persists after following these steps, it may be beneficial to consult with an SAP expert or reach out to SAP support for further assistance.