How To Fix IW491 - Purchase order already created: Reassignment not possible

SAP Error Message - Details

• Message type: E = Error

• Message class: IW - Order Processing

• Message number: 491

• Message text: Purchase order already created: Reassignment not possible

What causes this issue?

You want to reassign a material from one order operation to another.
This is not possible, however, because the account assignment at
operation level is activated for this order type. Since a purchase order
has already been created for this material and the costs have been
updated for the order operation, you cannot reassign this material to a
different order operation.

System Response

The material cannot be assigned to another operation.

How to fix this error?

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message IW491 - Purchase order already created: Reassignment not possible ?

  The SAP error message IW491: Purchase order already created: Reassignment not possible typically occurs in the context of maintenance orders or service orders when you attempt to reassign a maintenance order to a different cost center or internal order after a purchase order has already been created for that maintenance order.
  Cause:
  The primary cause of this error is that once a purchase order (PO) is created for a maintenance order, the system locks certain fields to maintain data integrity. Reassigning the maintenance order to a different cost center or internal order is not allowed because it could lead to inconsistencies in accounting and reporting.
  Solution:
  To resolve this error, you can consider the following approaches:
  
  
  Check Purchase Order Status: Verify if the purchase order is still open or if it has been fully processed. If it is still open, you may need to cancel or delete the purchase order before attempting to reassign the maintenance order.
  
  
  Reassign After PO Cancellation: If you need to reassign the maintenance order, cancel the existing purchase order first. Once the PO is canceled, you should be able to reassign the maintenance order to a different cost center or internal order.
  
  
  Create a New Maintenance Order: If the reassignment is critical and you cannot cancel the purchase order, consider creating a new maintenance order with the desired cost center or internal order and then create a new purchase order for that maintenance order.
  
  
  Consult with Your SAP Administrator: If you are unsure about the implications of canceling a purchase order or if you need to maintain historical data, consult with your SAP administrator or finance team for guidance.
  
  
  Review Configuration Settings: In some cases, the configuration settings in SAP may restrict certain actions. Review the settings related to purchase orders and maintenance orders to ensure they align with your business processes.
  
  
  Related Information:
  
  Transaction Codes: You may need to use transaction codes like IW32 (Change Order), IW31 (Create Order), ME23N (Display Purchase Order), and ME22N (Change Purchase Order) to manage orders and purchase orders.
  Documentation: Refer to SAP documentation or help files for detailed information on maintenance orders and purchase order processes.
  User Roles and Authorizations: Ensure that you have the necessary authorizations to perform actions related to purchase orders and maintenance orders.
  
  By following these steps, you should be able to address the IW491 error and proceed with your maintenance order management effectively.