Message type: E = Error
Message class:  CNV_PE - General messages for posting engine 
Message number: 743
Message text: Generation has started
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 "CNV_PE743 Generation has started" typically relates to the SAP Conversion Tools, particularly in the context of data migration or system conversion processes. This message indicates that a generation process has been initiated, which is part of the data conversion or migration activities.
Cause: Data Migration Process: This message often appears when you are running a data migration or conversion tool, such as the SAP S/4HANA Migration Cockpit or other related tools. Background Job: The message may indicate that a background job has been started for the generation of objects or data structures required for the migration.
Configuration Issues: There may be issues with the configuration of the migration tool or the source data that could lead to this message being displayed.
Solution: Monitor the Job: Check the status of the background job that was started. You can do this using transaction codes like SM37 to see if the job is running successfully
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