How To Fix MPE_OAN156 - Unknown certificate &1 assigned to operation activity

SAP Error Message - Details

• Message type: E = Error

• Message class: MPE_OAN - Operation Activity Network Messages

• Message number: 156

• Message text: Unknown certificate &1 assigned to operation activity

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.

Unfortunately, there isn't any extra information in this error notice.

What else can you do?

First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).

Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.

Smart SAP Assistant

• What is the cause and solution for SAP error message MPE_OAN156 - Unknown certificate &1 assigned to operation activity ?

  The SAP error message MPE_OAN156 indicates that there is an issue with an unknown certificate assigned to an operation activity. This typically occurs in the context of SAP's Manufacturing and Production Planning modules, particularly when dealing with certificates for operations in production orders or maintenance tasks.
  Cause:
  
  Missing Certificate: The certificate referenced in the operation activity does not exist in the system.
  Incorrect Configuration: The certificate may not be properly configured or linked to the operation activity.
  Data Inconsistency: There may be inconsistencies in the master data or configuration settings related to the operation or the certificate.
  Authorization Issues: The user may not have the necessary authorizations to access the certificate.
  
  Solution:
  
  
  Check Certificate Existence:
  
  Verify if the certificate mentioned in the error message exists in the system. You can do this by navigating to the relevant transaction (e.g., transaction code MCE1 for certificates) and checking if the certificate is listed.
  
  
  
  Correct Configuration:
  
  If the certificate does not exist, you may need to create it or correct the assignment in the operation activity. Ensure that the operation activity is correctly linked to the appropriate certificate.
  
  
  
  Review Master Data:
  
  Check the master data for the operation and ensure that all necessary fields are filled out correctly. This includes checking the routing and the work center associated with the operation.
  
  
  
  Authorization Check:
  
  Ensure that the user has the necessary authorizations to view and use the certificate. This may involve checking user roles and permissions in the SAP system.
  
  
  
  Consult Documentation:
  
  Refer to SAP documentation or help resources for specific guidance on managing certificates and operation activities.
  
  
  
  Contact Support:
  
  If the issue persists after checking the above points, consider reaching out to your SAP support team or consulting SAP Notes for any known issues related to this error.
  
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as MCE1 (for managing certificates), CO02 (for changing production orders), and CR02 (for changing routing).
  SAP Notes: Search for SAP Notes related to MPE_OAN156 for any patches or updates that may address this issue.
  User Manuals: Review user manuals or training materials related to production planning and operations management in SAP.
  
  By following these steps, you should be able to identify and resolve the issue related to the unknown certificate assigned to the operation activity.