How To Fix CM121 - Reallocation to the referenced operation & is not possible.

SAP Error Message - Details

• Message type: E = Error

• Message class: CM - Task list messages: Material component allocations

• Message number: 121

• Message text: Reallocation to the referenced operation & is not possible.

What causes this issue?

The material component you want to reallocate is allocated to an
operation which is referenced from an operation set. Material
components that are allocted to referenced operations cannot be changed
in the routing containing the reference.

How to fix this error?

If you want to reallocate the material component, you can do this by
maintaining the reference operation set. Note, however, that the
change is valid for all routings containing a reference to the
operation set.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CM121 - Reallocation to the referenced operation & is not possible. ?

  The SAP error message CM121 ("Reallocation to the referenced operation & is not possible") typically occurs in the context of production planning and control, particularly when dealing with capacity planning and scheduling in SAP. This error indicates that there is an issue with reallocating resources or operations in a production order or a related process.
  Causes of CM121 Error
  
  
  Capacity Constraints: The operation you are trying to reallocate may exceed the available capacity of the work center or resource. This can happen if the work center is already overloaded with other operations.
  
  
  Status of the Operation: The operation you are trying to reallocate may be in a status that does not allow for reallocation (e.g., it may be completed, closed, or in a different phase).
  
  
  Dependencies and Sequencing: There may be dependencies between operations that prevent the reallocation. For example, if the operation is dependent on the completion of a previous operation, it cannot be moved until that operation is finished.
  
  
  Incorrect Configuration: There may be configuration issues in the routing or work center settings that prevent the operation from being reallocated.
  
  
  Missing or Incorrect Data: If there are missing or incorrect data entries in the production order, routing, or work center, it can lead to this error.
  
  
  Solutions to CM121 Error
  
  
  Check Capacity Availability: Review the capacity of the work center to ensure that there is enough available capacity to accommodate the reallocation. You can do this by checking the capacity planning reports.
  
  
  Review Operation Status: Ensure that the operation you are trying to reallocate is in a status that allows for reallocation. If it is completed or closed, you may need to reverse the status before reallocating.
  
  
  Check Dependencies: Look for any dependencies or sequencing issues that may be preventing the reallocation. Ensure that all prerequisite operations are completed.
  
  
  Validate Configuration: Review the routing and work center configuration to ensure that they are set up correctly. Check for any discrepancies that may be causing the issue.
  
  
  Correct Data Entries: Ensure that all relevant data entries in the production order, routing, and work center are correct and complete. Make any necessary corrections.
  
  
  Use Transaction Codes: Utilize transaction codes like CO02 (Change Production Order) or CO03 (Display Production Order) to analyze the production order and make necessary adjustments.
  
  
  Related Information
  
  
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message. SAP frequently updates its knowledge base with solutions to common problems.
  
  
  Documentation: Refer to SAP documentation on production planning and control for more detailed information on managing operations and capacity.
  
  
  Consult with SAP Support: If the issue persists after trying the above solutions, consider reaching out to SAP support for further assistance.
  
  
  By following these steps, you should be able to identify the cause of the CM121 error and implement a solution to resolve it.