Message type: E = Error
Message class:  CNV_CMIS_M - Message class for CMIS Migration 
Message number: 303
Message text: Error while providing new rules
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The SAP error message CNV_CMIS_M303 typically occurs during the process of data migration or conversion, particularly when using the SAP Conversion Tools or the SAP S/4HANA Migration Cockpit. This error indicates that there is an issue with the rules being provided for the data migration process.
Cause: The error can be caused by several factors, including: Invalid Rule Definition: The rules defined for the data migration may not be valid or may not conform to the expected format. Missing Required Fields: Some required fields in the rule definition may be missing, leading to the error. Data Type Mismatch: There may be a mismatch between the data types expected by the system and the data types provided in the rules.
Configuration Issues: There could be configuration issues in the migration cockpit or the conversion tools that are causing the error. Incompatibility with Source Data: The rules may not be compatible with the source data being migrated.
Solution: To resolve the
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