Message type: E = Error
Message class:  CNV_20211_CHECK - Messages for check functions (company conversion) 
Message number: 017
Message text: Double mapping entry provided for source value &1
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The SAP error message CNV_20211_CHECK017 indicates that there is a double mapping entry for a source value in a data conversion or migration process. This typically occurs during the use of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other conversion tools, where source values are mapped to target values.
Cause: The error arises when the same source value is mapped to multiple target values. This can happen due to: Duplicate Entries: There are duplicate entries in the mapping table or configuration where the same source value is associated with different target values. Incorrect Mapping Configuration: The mapping rules or configurations may have been set up incorrectly, leading to conflicting mappings. Data Quality Issues: The source data may contain inconsistencies or duplicates that were not addressed prior to the mapping process.
Solution: To resolve this error, you can take the following steps: Review Mapping Configuration: Check the mapping configuration for the specific source value mentioned
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