How To Fix FL395 - During RFCs or update, no exception classes can be used

SAP Error Message - Details

• Message type: E = Error

• Message class: FL - Function Builder messages

• Message number: 395

• Message text: During RFCs or update, no exception classes can be used

What causes this issue?

With update or RFC function modules, class-based exceptions are not
supported.
You will find details on class-based exceptions for RFC function modules
in Note 829230.

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?

Use classic exceptions.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message FL395 - During RFCs or update, no exception classes can be used ?

  The SAP error message FL395, which states "During RFCs or update, no exception classes can be used," typically occurs in the context of Remote Function Calls (RFCs) or update function modules in SAP. This error indicates that an exception class was used in a context where it is not allowed, specifically during an RFC or update processing.
  Cause:
  
  Use of Exception Classes: The error is primarily caused by the use of exception classes in a function module that is being called remotely (RFC) or in an update function module. In these contexts, only standard exceptions (like CX_SY_NO_HANDLER, CX_SY_OPEN_SQL_DB, etc.) can be used.
  Improper Error Handling: If the function module is designed to handle exceptions using custom exception classes, it will lead to this error when invoked via RFC or update.
  
  Solution:
  
  Review Function Module: Check the function module that is causing the error. Ensure that it does not use any custom exception classes. Instead, use standard exceptions for error handling.
  Modify Exception Handling: If you need to handle specific errors, consider using standard exceptions or return error codes instead of raising exceptions.
  Testing: After making changes, test the function module both in the local environment and through RFC calls to ensure that the error is resolved.
  
  Related Information:
  
  RFC and Update Function Modules: Understand the difference between normal function modules and those designed for RFC or update processing. RFC function modules are called from remote systems, while update function modules are used for asynchronous processing.
  SAP Documentation: Refer to SAP's official documentation for guidelines on exception handling in RFC and update function modules.
  Debugging: Use transaction codes like SE37 (Function Builder) to analyze the function module and SE80 (Object Navigator) to check for related objects and dependencies.
  
  By following these steps, you should be able to resolve the FL395 error and ensure proper error handling in your SAP function modules.