Message type: E = Error
Message class:  CNVMBTPEM - PEM (Process Execution Manager) 
Message number: 020
Message text: &1 has not finished predecessors
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 CNVMBTPEM020 indicates that a specific process or task has not completed its predecessor tasks. This error typically arises in the context of data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error occurs when: A task that is supposed to run has dependencies on other tasks that have not yet been completed. The predecessor tasks may have failed, been skipped, or are still in progress. There may be issues with the configuration or sequencing of the tasks in the migration process.
Solution: To resolve the error, you can follow these steps: Check Task Status: Review the status of the predecessor tasks. Ensure that all required tasks have been completed successfully before the current task is executed. Review Logs: Look at the logs for the predecessor tasks to identify any errors or issues that may have caused them to fail or not complete. Re-run Predecessor Tasks: If any
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