Message type: E = Error
Message class:  CNV_OM - Messages for Objectbased Migration 
Message number: 070
Message text: Migration environment with mass transfer ID &1 already existing
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The SAP error message CNV_OM070 indicates that there is an existing migration environment associated with the specified mass transfer ID. This typically occurs during data migration processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error is caused by the following scenarios: Duplicate Migration Environment: A migration environment with the same mass transfer ID already exists in the system. This can happen if a previous migration attempt was not completed or was interrupted, leaving the environment in a state that prevents new migrations with the same ID. Incorrect Cleanup: If the previous migration process was not properly cleaned up or deleted, it can lead to conflicts when trying to create a new migration environment.
Solution: To resolve this error, you can take the following steps: Check Existing Migration Environments: Use transaction code LTMC (for Migration Cockpit) or relevant transaction codes to check for existing migration environments. Look for the mass transfer ID mentioned in
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