How To Fix CN838 - Several start/target activities exist

SAP Error Message - Details

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 838

• Message text: Several start/target activities exist

What causes this issue?

The network which is to become a subnetwork has several start and/or
finish (target) activities.
In this situation, the system creates relationships to all start and/or
finish (target) activities.

System Response

INCLUDE 'NA_ALLG_FUNKTION' OBJECT DOKU ID TX

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CN838 - Several start/target activities exist ?

  The SAP error message CN838 ("Several start/target activities exist") typically occurs in the context of project management within SAP, particularly when dealing with network activities in Project System (PS). This error indicates that there are multiple activities that are defined as either start or target activities for a given network, which can lead to ambiguity in scheduling and planning.
  Cause:
  
  Multiple Start Activities: The network may have more than one activity defined as a start activity, which confuses the system about which activity should be the actual starting point.
  Multiple Target Activities: Similarly, if there are multiple target activities defined, the system cannot determine which one should be the endpoint of the network.
  Incorrect Network Configuration: The network structure may not be configured correctly, leading to overlapping or conflicting definitions of activities.
  
  Solution:
  
  Review Network Activities: Go to the network in question and review the activities defined. Ensure that there is only one start activity and one target activity.
  Adjust Activity Settings: If you find multiple start or target activities, you will need to adjust the settings:
  
  Change Activity Type: If an activity is incorrectly marked as a start or target activity, change its type accordingly.
  Delete or Merge Activities: If there are redundant activities, consider deleting or merging them to simplify the network structure.
  
  
  Check Dependencies: Ensure that the dependencies between activities are correctly defined. This includes checking for any constraints that may lead to multiple start or target activities.
  Recreate the Network: In some cases, if the network is too complex or incorrectly set up, it may be easier to recreate the network from scratch with the correct definitions.
  
  Related Information:
  
  Transaction Codes: You can use transaction codes like CN21 (Create Network), CN22 (Change Network), and CN03 (Display Network) to manage network activities.
  Documentation: Refer to SAP documentation or help files for detailed guidance on network planning and activity management.
  SAP Notes: Check for any relevant SAP Notes that may address specific issues or bugs related to this error message.
  User Forums: Engage with SAP community forums or user groups for insights and solutions shared by other users who may have encountered the same issue.
  
  By following these steps, you should be able to resolve the CN838 error and ensure that your project network is correctly configured.