Message type: E = Error
Message class:  CNV20305 - Messages for conversion packages in CO 
Message number: 300
Message text: *** Messages for BPs ***
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The SAP error message CNV20305300 is related to Business Partner (BP) data during a data migration or conversion process, typically encountered in the context of SAP S/4HANA migrations or when using the SAP S/4HANA Migration Cockpit. This error message indicates that there are issues with the Business Partner data that need to be addressed.
Cause: The error message CNV20305300 usually arises due to one or more of the following reasons: Missing Required Fields: Certain mandatory fields for Business Partner creation may not be filled in the source data. Data Format Issues: The data format for specific fields may not comply with the expected format in SAP. Duplicate Entries: There may be duplicate Business Partner entries in the source data that violate uniqueness constraints. Inconsistent Data: The data may not be consistent with the rules defined in the target system, such as invalid combinations of data or incorrect relationships.
Configuration Issues: The Business Partner settings in the target
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