Message type: E = Error
Message class:  CNV_MBT - PCL message class 
Message number: 321
Message text: Statua change of foreign activity &1 in package &2,phase &3 not allowed
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The SAP error message CNV_MBT321 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 attempt to change the status of a foreign activity in a specific package and phase, which is not allowed.
Cause: Status Change Restrictions: The error arises when there is an attempt to change the status of an activity that is not permitted due to the current state of the migration process. This could be due to dependencies on other activities or phases that have not been completed or are locked. Incorrect Sequence of Operations: The migration process may have been executed out of the intended sequence, leading to attempts to modify statuses that should remain unchanged until certain conditions are met.
Configuration Issues: There may be configuration settings or rules in the migration cockpit that restrict certain actions based on the current
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