Message type: E = Error
Message class:  CNV20551 - message for package 20551 (company code delete) 
Message number: 757
Message text: No Table changed
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The SAP error message CNV20551757 "No Table changed" typically occurs during data migration or conversion processes, particularly when using SAP's tools for data transfer, such as the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that the system did not find any changes in the specified table during the migration process.
Cause: No Data Changes: The most common cause is that the source table does not contain any data that needs to be migrated or updated. This can happen if the data has already been migrated or if the source system is empty. Incorrect Configuration: There may be an issue with the configuration of the migration project, such as incorrect mapping or selection criteria that do not match any records in the source table. Data Filters: Filters applied during the migration process may exclude all records, leading to no changes being detected. Technical Issues: There could be underlying technical issues, such
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