How To Fix WA635 - Type linkage betw. & & and &: Not possible to change receiver funct.mod.&

SAP Error Message - Details

• Message type: E = Error

• Message class: WA - Messages from Workflow Event Manager

• Message number: 635

• Message text: Type linkage betw. & & and &: Not possible to change receiver funct.mod.&

What causes this issue?

The function module which is to be called so that the event can be
received by the receiver type (
<DS:GLOS.3526B12EAFAB52B9E10000009B38F974>receiver function module</>)
cannot be changed for the specified type linkage between object type
and event and the specified receiver type.

System Response

The action was terminated, the receiver function module is not changed.

How to fix this error?

Check whether the specified type linkage exists.
INCLUDE NA_WF-ADMINISTRATOR OBJECT DOKU ID TX

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message WA635 - Type linkage betw. & & and &: Not possible to change receiver funct.mod.& ?

  Certainly! Here's a detailed explanation for the SAP error message:
  
  SAP Error Message:
  WA635 Type linkage betw. & & and &: Not possible to change receiver funct.mod.&
  
  Meaning / Cause:
  This error occurs during the activation or modification of function modules that are linked via type linkage (also known as type group linkage or type pool linkage). The message indicates that there is a type linkage between certain function modules or interfaces, and due to this linkage, it is not possible to change the receiver function module.
  In SAP, function modules can be linked by types, meaning that the interface (parameters, types) of one function module depends on or is linked to another. If you try to change the receiver function module's interface or signature in a way that breaks this linkage, the system prevents it to maintain consistency and avoid runtime errors.
  
  Typical Scenarios:
  
  You are trying to change the interface of a function module that is linked to another function module via a type group or type pool.
  The function module is part of a function group or a set of function modules that share common types.
  The system detects that changing the receiver function module would break the type linkage.
  
  
  Solution / How to Fix:
  
  
  Check the Type Linkage:
  
  Identify the function modules involved in the linkage (the message will show the names in place of the placeholders &).
  Use transaction SE37 or SE80 to check the interfaces of the function modules.
  Check if the function modules share a common type group or type pool.
  
  
  
  Avoid Changing the Receiver Function Module Interface:
  
  If the function module is linked, you cannot change its interface arbitrarily.
  Instead, consider changing the calling function module or the type group if necessary.
  
  
  
  Adjust the Type Group or Type Pool:
  
  If the change is necessary, you may need to adjust the type group or type pool that defines the common types.
  Be cautious: changing type groups affects all function modules linked to it.
  
  
  
  Use Transport Organizer / Version Management:
  
  Sometimes, inconsistencies arise due to transport or version conflicts.
  Check if the function modules are locked or if there are transport requests pending.
  
  
  
  Consult SAP Notes:
  
  Search for SAP Notes related to WA635 for any known issues or patches.
  
  
  
  If urgent and safe, delete and recreate:
  
  As a last resort, if the function module is not heavily used, you might delete and recreate it with the desired interface.
  This is risky and should be done only if you understand the impact.
  
  
  
  
  Additional Information:
  
  Type linkage is a mechanism in SAP to ensure that function modules sharing common data types remain consistent.
  This error is a safeguard to prevent runtime errors due to inconsistent interfaces.
  Always perform interface changes in a controlled manner, preferably in a development system with proper testing.
  Use SE37 (Function Builder) to analyze function modules and their interfaces.
  Use SE11 to check data types and type groups.
  
  
  Summary:
  
  
  
  Aspect
  Description
  
  
  
  
  Cause
  Attempt to change a receiver function module's interface that is linked by type linkage.
  
  
  Effect
  System prevents the change to maintain interface consistency.
  
  
  Solution
  Review and adjust type groups or calling modules; avoid direct changes to linked receiver.
  
  
  Tools
  SE37, SE80, SE11, Transport Organizer, SAP Notes.
  
  
  
  
  If you provide the exact function module names or the context in which this error occurs, I can help you with more specific guidance.