Message type: E = Error
Message class:  FBS_SE - Messages for Transfer of FIN-MDM Data 
Message number: 121
Message text: Data contains errors (table &1. field &2, value &3)
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The SAP error message FBS_SE121 indicates that there are data errors in a specific table and field, which prevents the successful execution of a transaction or process. This error typically arises during financial postings or data uploads when the system detects invalid or inconsistent data.
Cause: The error message FBS_SE121 is triggered due to one or more of the following reasons: Invalid Data Format: The value being entered in the specified field does not conform to the expected format (e.g., incorrect date format, numeric values where text is expected). Missing Required Fields: A required field may be empty or not filled out correctly. Data Consistency Issues: The value may not exist in the corresponding master data or configuration tables (e.g., a GL account that is not valid). Business Rules Violation: The data may violate specific business rules defined in the system (e.g., posting periods, document types). Custom Validation Logic: Custom validations implemented in user exits or BAdIs
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