Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 345
Message text: & confirms that remaining old set data is not relevant for conversion
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The SAP error message CNV_20100345 typically relates to data conversion issues during a system migration or upgrade, particularly in the context of the SAP S/4HANA conversion process. This error indicates that there is old set data that is not relevant for the conversion process.
Cause: The error CNV_20100345 usually arises due to the presence of legacy data or old set data that is no longer needed or relevant for the new system environment. This can happen when: Data Redundancy: There are entries in the database that are not required for the new system. Inconsistent Data: The old data may not meet the new data model requirements of the target system.
Configuration Issues: The conversion program may not be configured correctly to handle certain data sets.
Solution: To resolve this error, you can take the following steps: Data Cleanup: Review the old set data and determine if it can be deleted or archived. This may involve: Identifying obsolete data that
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