Message type: E = Error
Message class:  CNV_MBT - PCL message class 
Message number: 021
Message text: Error in table entry for phase &
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.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
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The SAP error message CNV_MBT021 typically occurs during a data migration or conversion process, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that there is an issue with a specific table entry during a particular phase of the migration process.
Cause: The error can be caused by several factors, including: Data Integrity Issues: The data being migrated may have integrity issues, such as missing mandatory fields, incorrect data types, or foreign key violations. Configuration Problems: There may be configuration issues in the source or target system that prevent the migration from proceeding smoothly. Mapping Errors: Incorrect mapping of fields between the source and target systems can lead to this error. Custom Code or Enhancements: If there are custom developments or enhancements in the source system, they may not be compatible with the migration process.
Solution: To resolve the CNV_MBT021 error, you can follow these steps: Check the Logs: Review the detailed logs provided
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