Message type: E = Error
Message class:  CNV_NCE_BAS - Number conversion engine: messages 
Message number: 464
Message text: Valid mapping values saved for &1
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message CNV_NCE_BAS464 typically indicates that there are valid mapping values saved for a specific object or field in the context of a data conversion or migration process. This message is often encountered during the execution of the SAP Data Migration or Conversion tools, particularly in the context of the SAP S/4HANA migration.
Cause: The error message suggests that the system has detected that there are existing valid mapping values for the specified object (denoted by &1). This could occur due to several reasons: Duplicate Entries: There may be duplicate mapping entries for the same object, which can lead to confusion in the data conversion process. Incomplete Mapping: The mapping process may not have been completed correctly, leading to inconsistencies in the mapping values.
Configuration Issues: There may be issues with the configuration of the data migration tool or the mapping settings.
Solution: To resolve the CNV_NCE_BAS464 error, you can take the following steps: Check Mapping
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