Message type: E = Error
Message class:  CNV20551 - message for package 20551 (company code delete) 
Message number: 457
Message text: Error; differentiator without related structure information (&)
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message CNV20551457, which states "Error; differentiator without related structure information (&)," typically occurs during data migration or conversion processes, particularly when using SAP's tools for data transformation or migration, such as the SAP S/4HANA Migration Cockpit or other data conversion tools.
Cause: This error generally indicates that there is a mismatch or inconsistency in the data structure definitions. Specifically, it suggests that a differentiator (which is a field or attribute used to distinguish between different records or data entries) is being referenced without the necessary accompanying structure information. This can happen due to: Missing Configuration: The required structure or mapping for the differentiator is not defined in the migration or conversion settings. Incorrect Data Mapping: The data being migrated does not align with the expected structure, leading to confusion in how the differentiator should be processed. Incompatible Data Types: The data types of the differentiator and the expected structure may not match,
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