Message type: E = Error
Message class:  BOS01 - Customer BOS Processing 
Message number: 303
Message text: Select the schedule line allowed for document item with BOS
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The SAP error message BOS01303, which states "Select the schedule line allowed for document item with BOS," typically occurs in the context of the SAP Business Order System (BOS) when there is an issue with the schedule lines associated with a document item. This error can arise during various processes, such as creating or modifying sales orders, purchase orders, or production orders.
Cause: Invalid Schedule Line: The schedule line you are trying to select may not be valid for the specific document item. This can happen if the schedule line does not meet the criteria set in the system.
Configuration Issues: There may be configuration settings in the system that restrict the selection of certain schedule lines based on the document type or item category. Missing Data: Required data for the schedule line may be missing, such as delivery dates, quantities, or other relevant information. Document Status: The status of the document may not allow
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