Message type: E = Error
Message class:  CNV20305 - Messages for conversion packages in CO 
Message number: 058
Message text: CoAr &1 was unnecessarily included in number range table CNV_NRIV_O.
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The SAP error message CNV20305058 indicates that a specific object (in this case, CoAr &1) has been unnecessarily included in the number range table CNV_NRIV_O. This typically occurs during data migration or conversion processes, particularly when using SAP's Conversion Tools.
Cause: Incorrect Configuration: The object might have been mistakenly added to the number range table during the configuration of the data migration process. Redundant Entries: The object may not require a number range assignment, leading to its unnecessary inclusion. Data Migration Process: This error often arises during the execution of a migration project where certain objects are not properly defined or are incorrectly set up.
Solution: Review Configuration: Check the configuration settings for the number range object in question. Ensure that CoAr &1 is indeed required in the number range table. Remove Unnecessary Entries: If it is confirmed that the object does not need to be included, you can remove it from the CNV_NRIV_O table. This can
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