Message type: E = Error
Message class:  CNV20551 - message for package 20551 (company code delete) 
Message number: 603
Message text: Error when unlocking &1.
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The SAP error message CNV20551603 typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that there is an issue with unlocking a specific object or entity (denoted by &1) in the system.
Cause: The error can be caused by several factors, including: Locking Issues: The object you are trying to unlock is currently locked by another user or process. Authorization Problems: The user executing the operation may not have the necessary authorizations to unlock the object. Technical Issues: There may be underlying technical issues in the system, such as database locks or inconsistencies in the migration process. Configuration Errors: Incorrect configuration settings in the migration tool or related components can lead to this error.
Solution: To resolve the CNV20551603 error, you can try the following steps: Check Locks: Use transaction code SM12 to check for any locks on the object. If you find that the object is
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