Message type: E = Error
Message class:  MM_PUR_PO_APV_MSG - Approval Gateway Services: General Message Class 
Message number: 016
Message text: You are not authorized to display this purchasing document
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The SAP error message MM_PUR_PO_APV_MSG016, which states "You are not authorized to display this purchasing document," typically indicates that the user attempting to access a purchasing document (such as a purchase order) does not have the necessary authorizations to view that document.
Cause: Authorization Issues: The user’s role or profile does not include the necessary authorizations to view the specific purchasing document. Document Status: The document may be in a status that restricts access (e.g., it may be locked or in a state that requires special permissions). User Role Configuration: The user may not be assigned to the correct organizational units or may lack the necessary permissions in the authorization objects related to purchasing.
Solution: Check User Authorizations: Contact your SAP security administrator to review the user’s roles and authorizations. Ensure that the user has the necessary authorizations for the relevant authorization objects, such as M_BEST_BSA (Purchasing Document: Authorization for Document Type) and M_BEST_EKO (Purchasing Document: Authorization for
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