Message type: E = Error
Message class:  CNVMBT - Messages for MBT/API/PCL 
Message number: 073
Message text: Generation of object(s) started, see monitor to get the progress
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The SAP error message CNVMBT073 indicates that the generation of objects has started, and you should check the monitor to see the progress of this operation. This message is typically associated with the SAP Migration Cockpit or data migration processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: Long-running Process: The message is not necessarily an error but rather an informational message indicating that the generation of objects (like data structures, tables, or other artifacts) is in progress. This can take time depending on the volume of data and complexity of the objects being generated. System Performance: If the system is under heavy load or if there are performance issues, the generation process may take longer than expected.
Configuration Issues: There may be configuration issues or missing prerequisites that could affect the generation process.
Solution: Check the Monitor: Go to the relevant transaction or tool (like the SAP Migration Cockpit) and check
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