Message type: E = Error
Message class:  FCO_SFIN - FI-CO Simplified Financials 
Message number: 050
Message text: Mark one line as default line
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The SAP error message FCO_SFIN050, which states "Mark one line as default line," typically occurs in the context of financial document processing, particularly when dealing with line items in a financial transaction or document. This error indicates that the system requires at least one line item to be marked as the default line for processing.
Cause: Missing Default Line: The error arises when there are multiple line items in a financial document, but none of them are marked as the default line. The system needs a default line to proceed with certain operations, such as posting or saving the document.
Configuration Issues: There may be configuration settings in the financial module that require a default line to be specified for certain types of transactions. User Input Error: The user may have inadvertently skipped marking a line as default when creating or editing the document.
Solution: Mark a Line as Default: Open the financial document where the error
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