Message type: E = Error
Message class:  FI_E - Message Class for FM English Developers 
Message number: 304
Message text: Any kind of Sets are not allowed as target fields
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The SAP error message FI_E304, which states "Any kind of Sets are not allowed as target fields," typically occurs in the context of financial accounting or reporting when you are trying to assign a set (like a set of values or a set of characteristics) to a target field that does not support it. This error is often encountered in the context of data transfer, report generation, or configuration settings in SAP.
Cause: Incompatible Data Types: The target field you are trying to populate or use does not accept sets as valid input. This could be due to the field being designed to accept only single values or specific data types.
Configuration Issues: There may be a misconfiguration in the settings where a set is being incorrectly assigned to a field that does not support it. Custom Development: If there are custom programs or enhancements, they might be incorrectly handling data types, leading to
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