How To Fix W3_TOOL091 - The & function is not an RFC module

SAP Error Message - Details

• Message type: E = Error

• Message class: W3_TOOL - ITS: Maintenance Messages

• Message number: 091

• Message text: The & function is not an RFC module

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message W3_TOOL091 - The & function is not an RFC module ?

  Certainly! Here's a detailed explanation for the SAP error message:
  
  SAP Error Message:
  W3_TOOL091 The & function is not an RFC module
  
  Cause:
  This error occurs when a function module that is expected to be an RFC (Remote Function Call) enabled module is not actually flagged as RFC-enabled in the SAP system. In other words, the system is trying to call a function module remotely (via RFC), but the function module does not have the "Remote-Enabled Module" attribute set.
  The placeholder & in the message will be replaced by the actual function module name when the error occurs.
  
  Explanation:
  
  RFC modules are function modules that are explicitly enabled for remote calls.
  If a function module is not marked as remote-enabled, it cannot be called from outside the SAP system or from other SAP systems.
  This error typically arises during integration scenarios, such as when using SAP Web Services, SAP PI/PO, or any external system trying to call an SAP function module remotely.
  
  
  Solution:
  
  
  Check the Function Module Attributes:
  
  Go to transaction SE37 (Function Builder).
  Enter the function module name (the one shown in the error message).
  Click on Attributes.
  Verify if the checkbox Remote-Enabled Module is selected.
  
  
  
  If Not Remote-Enabled:
  
  If the function module is not remote-enabled, and it needs to be called remotely, you must:
  
  Change the function module attributes to enable remote calls.
  To do this, select the Remote-Enabled Module checkbox.
  Save and activate the function module.
  
  
  
  
  
  If You Cannot Change the Function Module:
  
  Sometimes, the function module is standard SAP or should not be remote-enabled.
  In this case, check if the correct function module is being called.
  There might be a configuration or coding error where the wrong function module is referenced.
  Correct the calling program or configuration to use the appropriate RFC-enabled function module.
  
  
  
  Transport Changes:
  
  If you make changes, ensure they are transported properly across the landscape (DEV ? QA ? PROD).
  
  
  
  
  Additional Information:
  
  Transaction SE37: Used to display and maintain function modules.
  Remote-Enabled Module: This attribute allows the function module to be called via RFC.
  RFC (Remote Function Call): A protocol to call functions in a remote SAP system or external system.
  Common Scenario: This error often appears in web service calls, ALE/IDoc processing, or custom developments involving RFC.
  
  
  Summary:
  
  
  
  Aspect
  Details
  
  
  
  
  Error
  W3_TOOL091 The & function is not an RFC module
  
  
  Cause
  Function module is not flagged as remote-enabled but is called via RFC
  
  
  Solution
  Enable "Remote-Enabled Module" attribute in SE37 or correct the function module being called
  
  
  Transaction
  SE37 (Function Builder)
  
  
  
  
  If you need help identifying the function module or further troubleshooting, please provide the exact function module name or the context in which the error occurs.