Message type: E = Error
Message class:  CNV20200 - Messages for development class CNV_20200 
Message number: 136
Message text: &1 not yet known! Conversion rule for &2=&3 not applicable!
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The SAP error message CNV20200136 typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that a specific conversion rule for a particular field or data element is not applicable or has not been defined in the system.
Cause: Missing Conversion Rule: The conversion rule for the specified field (&2) and value (&3) is not defined in the migration settings. Data Incompatibility: The data being migrated may not meet the expected format or criteria defined in the conversion rules.
Configuration Issues: There may be issues with the configuration of the migration project or the mapping of fields between the source and target systems.
Solution: Check Conversion Rules: Review the conversion rules defined in the migration project. Ensure that there is a valid rule for the specified field and value. If necessary, create or modify the conversion rule to accommodate the data being migrated. Data Validation: Validate the data
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