Message type: E = Error
Message class:  /SAPAPO/FOT -  
Message number: 813
Message text: Product cannot be blank
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The SAP error message /SAPAPO/FOT813 Product cannot be blank typically occurs in the context of SAP Advanced Planning and Optimization (APO) when a user attempts to perform an action that requires a product identifier, but the product field is left empty or not properly populated.
Cause: Missing Product Information: The most common cause is that the product field is not filled in the transaction or report you are trying to execute. Data Entry Error: The user may have inadvertently skipped the product field or made a mistake while entering data.
Configuration Issues: There may be issues with the configuration of the APO system that prevent the product from being recognized. Authorization Issues: Sometimes, the user may not have the necessary authorizations to view or select products.
Solution: Check Input Fields: Ensure that the product field is filled in correctly. If you are using a selection screen, make sure to enter a valid product ID. Validate Product Master Data:
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