Message type: E = Error
Message class:  CNV_MBT_XAPP_A - Message classes for all Cross-Application functions 
Message number: 064
Message text: Process tree change for activity already completed in previous run
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The SAP error message CNV_MBT_XAPP_A064 typically occurs in the context of data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that there is an attempt to change the process tree for an activity that has already been completed in a previous run.
Cause: Process Tree Modification: The error arises when there is an attempt to modify or re-execute a migration activity that has already been marked as completed in a previous execution. This can happen if the migration process is not properly sequenced or if there are inconsistencies in the migration logs. Data Consistency Issues: If the data or configuration has changed since the last run, it may lead to conflicts when trying to reprocess completed activities. Incorrect Configuration: Sometimes, the configuration settings for the migration process may not align with the current state of the data or the migration activities.
Solution: Check Migration Logs:
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