Message type: E = Error
Message class:  /SAPAPO/SALES -  
Message number: 519
Message text: Customer requirement &4: Schedule line intended for update
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The SAP error message /SAPAPO/SALES519 typically occurs in the context of Advanced Planning and Optimization (APO) when there is an issue with the scheduling of customer requirements. The message indicates that a schedule line intended for update is not being processed correctly.
Cause: The error can be caused by several factors, including: Inconsistent Data: There may be inconsistencies in the data related to the customer requirement or the schedule line. Missing Configuration: The necessary configuration for handling schedule lines in the APO system may not be set up correctly. Locked Objects: The schedule line or related objects may be locked by another process or user, preventing updates. Incorrect Settings: The settings for the product or the planning area may not be aligned with the requirements of the customer order. Integration Issues: There may be issues with the integration between SAP ERP and SAP APO, leading to problems in data transfer.
Solution: To resolve the error, you can take the
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