How To Fix PPEENG156 - &1 between &2 and &3 not allowed because it causes recursion

SAP Error Message - Details

• Message type: E = Error

• Message class: PPEENG - iPPE Engine Messages

• Message number: 156

• Message text: &1 between &2 and &3 not allowed because it causes recursion

What causes this issue?

You have tried to create a relationship of type &v1& between the
objects &v2& and &v3&. This relation causes recursion in the iPPE
relationship network.

System Response

The system does not allow you to create the relationship of type &v1&
between the objects &v2& and &v3&.

How to fix this error?

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

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 PPEENG156 - &1 between &2 and &3 not allowed because it causes recursion ?

  The SAP error message PPEENG156 indicates that there is a recursion issue in the planning process. This typically occurs in the context of production planning or project planning when a certain operation or task is trying to reference itself or is involved in a circular dependency with other operations or tasks.
  Cause:
  The error message "PPEENG156 &1 between &2 and &3 not allowed because it causes recursion" usually arises due to:
  
  
  Circular Dependencies: There are operations or tasks that depend on each other in a way that creates a loop. For example, if Task A depends on Task B, and Task B also depends on Task A, this creates a recursion.
  
  
  Incorrect Configuration: The configuration of the planning parameters or the relationships between tasks may not be set up correctly, leading to unintended dependencies.
  
  
  Data Integrity Issues: There may be issues with the data in the system, such as incorrect links between operations or tasks.
  
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Review Task Dependencies: Check the dependencies between the tasks or operations involved. Ensure that there are no circular references. You can do this by reviewing the task relationships in the planning board or project structure.
  
  
  Adjust Planning Parameters: If the dependencies are correct but still causing issues, review the planning parameters and settings. Ensure that they are configured correctly to avoid recursion.
  
  
  Data Validation: Validate the data in the system to ensure that there are no inconsistencies or errors in the task definitions or relationships.
  
  
  Use Planning Tools: Utilize SAP planning tools to visualize the task dependencies. This can help identify any circular dependencies that may not be immediately obvious.
  
  
  Consult Documentation: Refer to SAP documentation or help resources for specific guidance on the error message and its context. This can provide insights into best practices for setting up tasks and dependencies.
  
  
  Seek Support: If the issue persists, consider reaching out to SAP support or your internal SAP team for further assistance. They may have additional tools or insights to help resolve the issue.
  
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional troubleshooting steps.
  Transaction Codes: Familiarize yourself with transaction codes related to planning, such as CTP (Capacity Planning) or CPO (Capacity Planning Overview), which may help in analyzing the issue.
  Training and Documentation: Ensure that users involved in planning are trained on best practices for setting up tasks and dependencies to avoid such issues in the future.
  
  By following these steps, you should be able to identify and resolve the cause of the PPEENG156 error in your SAP system.