How To Fix MPE_OAN061 - Predecessor &1 does not exist in the operation activity network

SAP Error Message - Details

• Message type: E = Error

• Message class: MPE_OAN - Operation Activity Network Messages

• Message number: 061

• Message text: Predecessor &1 does not exist in the operation activity network

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

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Smart SAP Assistant

• What is the cause and solution for SAP error message MPE_OAN061 - Predecessor &1 does not exist in the operation activity network ?

  The SAP error message MPE_OAN061 indicates that there is a problem with the operation activity network in a project or production order. Specifically, it means that a predecessor operation that is expected to exist does not exist in the network. This can occur in various scenarios, such as when you are trying to create or modify an operation in a project or production order.
  Cause:
  
  Missing Predecessor: The predecessor operation that is referenced does not exist in the operation activity network. This could be due to a deletion or an incorrect reference.
  Incorrect Configuration: The operation might be incorrectly configured, leading to a reference to a non-existent predecessor.
  Data Inconsistency: There may be inconsistencies in the data, such as missing entries in the database or issues with the project structure.
  Incorrect Order of Operations: The operation might be trying to reference a predecessor that is not defined in the correct sequence.
  
  Solution:
  
  Check Operation Network: Verify the operation activity network to ensure that the predecessor operation exists. You can do this by navigating to the relevant project or production order and checking the operations listed.
  Correct Predecessor Reference: If the predecessor operation is missing, you may need to add it back into the network or correct the reference in the operation that is causing the error.
  Review Configuration: Ensure that the configuration of the operations is correct and that all necessary predecessors are defined.
  Data Consistency Check: Run a consistency check on the project or order to identify any discrepancies in the data.
  Recreate the Operation: If the issue persists, consider deleting the problematic operation and recreating it, ensuring that all predecessors are correctly defined.
  Consult Documentation: Refer to SAP documentation or help resources for specific guidance related to your version of SAP and the context in which the error occurs.
  
  Related Information:
  
  Transaction Codes: You may use transaction codes like CJ20N (Project Builder) or CO02 (Change Production Order) to navigate to the relevant project or order and check the operations.
  SAP Notes: Check for any relevant SAP Notes that might address this specific error or provide additional troubleshooting steps.
  User Forums: Consider visiting SAP community forums or user groups where similar issues may have been discussed, and solutions shared.
  
  If the problem persists after trying the above solutions, it may be beneficial to consult with your SAP support team or a technical consultant who can provide more in-depth assistance.