How To Fix CN837 - Relationships betw. activities in different alternatives are not allowed

SAP Error Message - Details

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 837

• Message text: Relationships betw. activities in different alternatives are not allowed

What causes this issue?

You have entered a relationship to another alternative of the standard
network. This is not allowed.

System Response

INCLUDE 'NA_ALLG_NOVERARBEITUNG' OBJECT DOKU ID TX

How to fix this error?

Enter a different alternative.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CN837 - Relationships betw. activities in different alternatives are not allowed ?

  The SAP error message CN837, which states "Relationships between activities in different alternatives are not allowed," typically occurs in the context of project management within SAP, particularly when dealing with network activities in Project System (PS) or similar modules.
  Cause:
  This error arises when you attempt to create a dependency (relationship) between activities that belong to different alternatives in a project. In SAP, alternatives are used to represent different scenarios or options for executing a project. Each alternative can have its own set of activities, and relationships (like finish-to-start, start-to-start, etc.) can only be established within the same alternative.
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Check Activity Alternatives: Review the activities involved in the relationship. Ensure that both activities are part of the same alternative. If they are not, you will need to either:
  
  Move one of the activities to the same alternative as the other.
  Create a new relationship that only involves activities within the same alternative.
  
  
  
  Modify Relationships: If you need to maintain the relationship but the activities must remain in different alternatives, consider whether the relationship is necessary. You may need to rethink the project structure or the dependencies.
  
  
  Use Project Structure: If your project requires complex relationships across alternatives, consider restructuring your project to better reflect the dependencies without violating the rules of alternatives.
  
  
  Consult Documentation: Refer to SAP documentation or help resources for more detailed guidance on managing alternatives and relationships in your specific version of SAP.
  
  
  Seek Help from SAP Support: If you are unable to resolve the issue, consider reaching out to your SAP support team or consulting with an SAP expert who can provide tailored assistance based on your project setup.
  
  
  Related Information:
  
  Project System (PS) Module: Understanding how the PS module handles alternatives and relationships can provide insights into best practices for project planning.
  Network Activities: Familiarize yourself with how network activities are structured in SAP, including the use of milestones and dependencies.
  SAP Notes and Knowledge Base: Check for any relevant SAP Notes that might address this error or provide additional context.
  
  By following these steps, you should be able to resolve the CN837 error and effectively manage your project activities within SAP.