How To Fix FL226 - Only compatible changes allowed for function module

FL226 - Overview

• Message type: E = Error

• Message class: FL - Function Builder messages

• Message number: 226

• Message text: Only compatible changes allowed for function module

What causes this issue?

You attempted to make an incompatible change to a function module that
has been released.

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?

Try to change the interface in a compatible way. For example, you could
add import and changing parameters, provided each has a default value
or is flagged as optional. Tables must also be flagged as optional.
Changes to the reference structures or to the "optional" flags of
existing parameters are not permitted.
If incompatible changes are unavoidable, make a copy of the function
module and continue your work using this copy. You can then make
changes without affecting the existing calls.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message FL226 - Only compatible changes allowed for function module ?

  The SAP error message FL226 ("Only compatible changes allowed for function module") typically occurs when there are incompatible changes made to a function module in SAP. This error is related to the versioning and compatibility rules that SAP enforces to ensure that changes to function modules do not break existing functionality or interfaces.
  
  Cause:
  The error can be triggered by several scenarios, including but not limited to:
  
  
  Incompatible Changes: Changes that alter the interface of the function module in a way that is not backward compatible. This includes:
  
  Changing the parameter types (e.g., from input to output).
  Changing the number of parameters.
  Changing the data types of existing parameters.
  Removing parameters.
  
  
  
  Transport Issues: If a function module is transported from one system to another and the target system has a different version of the function module, it may lead to this error.
  
  
  Version Conflicts: If there are multiple versions of a function module and an attempt is made to