How To Fix RTCMMD406 - Hierarchy level 1 cannot be defined as a category level

SAP Error Message - Details

• Message type: E = Error

• Message class: RTCMMD - Article Hierarchy

• Message number: 406

• Message text: Hierarchy level 1 cannot be defined as a category level

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message RTCMMD406 - Hierarchy level 1 cannot be defined as a category level ?

  The SAP error message RTCMMD406 indicates that there is an issue with the configuration of a hierarchy in the context of Master Data Management (MDM) or similar areas where hierarchical structures are used. Specifically, the error states that "Hierarchy level 1 cannot be defined as a category level." This typically means that the system is trying to assign a category level to the top level of a hierarchy, which is not allowed.
  Cause:
  
  Hierarchy Configuration: The error usually arises when the hierarchy is not configured correctly. In SAP, the top level of a hierarchy (level 1) is generally reserved for the overall category and cannot be treated as a sub-category or a category level.
  Data Model Issues: There may be issues with the data model where the hierarchy is defined, leading to conflicts in how levels are categorized.
  Incorrect Settings: The settings in the hierarchy definition may not align with the expected structure, leading to this error.
  
  Solution:
  
  Review Hierarchy Configuration: Check the configuration of the hierarchy in the relevant transaction (e.g., transaction code for maintaining hierarchies). Ensure that level 1 is set up correctly and is not being defined as a category level.
  Adjust Category Levels: If you need to define categories, ensure that they start from level 2 or below, as level 1 should remain as the top-level category.
  Consult Documentation: Refer to SAP documentation or help resources for guidance on how to properly set up hierarchies and category levels.
  Testing: After making changes, test the hierarchy to ensure that it functions as expected without triggering the error.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that might address this specific error or provide additional context on hierarchy configurations.
  SAP Community: Engage with the SAP Community forums where other users may have encountered similar issues and can provide insights or solutions.
  Training and Documentation: Consider reviewing training materials or documentation related to Master Data Management and hierarchy configurations in SAP to better understand the structure and requirements.
  
  If the issue persists after following these steps, it may be beneficial to consult with an SAP expert or your organization's SAP support team for further assistance.