How To Fix WER_CUST002 - Interface &1 doesn't implement interface &2.

SAP Error Message - Details

• Message type: E = Error

• Message class: WER_CUST -

• Message number: 002

• Message text: Interface &1 doesn't implement interface &2.

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message WER_CUST002 - Interface &1 doesn't implement interface &2. ?

  Certainly! Here's a detailed explanation for the SAP error message:
  
  SAP Error Message:
  WER_CUST002 Interface &1 doesn't implement interface &2.
  
  Meaning / Cause:
  This error occurs when a program or configuration expects an interface (let's call it Interface A) to implement another interface (Interface B), but Interface A does not actually implement Interface B.
  In other words, the system is trying to treat an interface as if it inherits or includes another interface, but this is not the case in the ABAP Dictionary or class/interface definitions.
  This often happens in scenarios involving:
  
  BAdI (Business Add-Ins) implementations
  Enhancement Frameworks
  Custom interfaces in ABAP Objects where interface inheritance is expected
  Configuration or coding errors where the wrong interface is assigned or referenced
  
  
  Typical Scenario:
  
  You have an interface ZIF_INTERFACE_A.
  The system expects ZIF_INTERFACE_A to implement ZIF_INTERFACE_B.
  But ZIF_INTERFACE_A does not list ZIF_INTERFACE_B in its interface inheritance.
  When the system checks this relationship (e.g., during runtime or activation), it throws this error.
  
  
  Solution:
  
  
  Check Interface Definitions:
  
  Go to transaction SE24 (Class Builder).
  Enter the interface name given in the error message as &1 (the first placeholder).
  Check the "Interfaces" tab to see which interfaces it implements.
  Verify if the interface &2 (the second placeholder) is listed.
  
  
  
  Add Missing Interface:
  
  If the interface &2 is missing, and logically &1 should implement &2, then:
  
  Modify interface &1 to include &2 as a super-interface.
  Save and activate the interface.
  
  
  
  
  
  Correct the Configuration or Code:
  
  If &1 should not implement &2, then check where this assumption is made.
  Correct the code or configuration to reference the correct interface.
  For example, in BAdI implementations, check the filter or interface assignment.
  
  
  
  Check for Transport or Activation Issues:
  
  Sometimes, the interface inheritance is changed but not transported or activated properly.
  Ensure all related objects are activated and transported correctly.
  
  
  
  
  Additional Information:
  
  Interface inheritance in ABAP: An interface can inherit from one or more other interfaces. This means it includes all methods and attributes of the super-interfaces.
  BAdI and Enhancement Framework: Many SAP enhancement points require interfaces to implement certain base interfaces to ensure compatibility.
  Debugging: You can debug the point where the error occurs to see which interface check fails.
  SAP Notes: Check SAP Notes or OSS messages if this error occurs in standard SAP code or after upgrades.
  
  
  Summary:
  
  
  
  Aspect
  Details
  
  
  
  
  Error
  Interface &1 doesn't implement interface &2
  
  
  Cause
  Interface inheritance missing or incorrect
  
  
  Solution
  Add missing interface inheritance or correct references
  
  
  Tools
  SE24 (Class Builder), SE80, Debugger
  
  
  Context
  BAdI, Enhancement Framework, Custom interfaces
  
  
  
  
  If you provide the actual interface names (&1 and &2), I can help you with more specific guidance.