How To Fix PPEACT642 - Hierarchy relationship is not allowed between &1 type &3 and &2 type &4

PPEACT642 - Overview

• Message type: E = Error

• Message class: PPEACT - Messages for iPPE ACT Application (Activities)

• Message number: 642

• Message text: Hierarchy relationship is not allowed between &1 type &3 and &2 type &4

What causes this issue?

The required hierarchy relationship is not available in Customizing.

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?

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 PPEACT642 - Hierarchy relationship is not allowed between &1 type &3 and &2 type &4 ?

  The SAP error message PPEACT642 indicates that there is an issue with the hierarchy relationship between two objects in the system. Specifically, it suggests that the relationship you are trying to establish between the two specified types is not permitted. This error typically occurs in the context of SAP's Product Lifecycle Management (PLM) or similar modules where hierarchical relationships between objects (like materials, BOMs, or other entities) are defined.
  
  Cause:
  The error message PPEACT642 is triggered when:
  
  You are trying to create a relationship between two object types that are not compatible. For example, you might be trying to link a material to a BOM in a way that is not allowed by the system's configuration.
  The object types involved do not support the hierarchical relationship you are attempting to establish. This could be due to predefined rules in the system or configuration settings that restrict certain types of relationships.
  
  
  Solution:
  To resolve this error, you