Message type: E = Error
Message class:  CNV_21543 - Administrator Group Rename 
Message number: 012
Message text: Multiple lines with old administrator group &1
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The SAP error message CNV_21543012 indicates that there are multiple lines associated with an old administrator group in the context of a data migration or conversion process. This error typically arises during the execution of a conversion program, particularly in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other data transfer processes.
Cause: The error is caused by the presence of multiple entries in the system that reference an old administrator group. This can happen due to: Data Duplication: There are duplicate entries in the source data that refer to the same old administrator group. Data Inconsistency: The data being migrated may have inconsistencies or errors that lead to multiple lines being created for the same group.
Configuration Issues: The configuration settings in the migration tool may not be set up correctly, leading to the system not being able to handle the old administrator group properly.
Solution: To resolve this
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