Message type: E = Error
Message class:  CNV_20700 - Material number conversion 
Message number: 019
Message text: Mapping not maintained for renaming material numbers
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The SAP error message CNV_20700019 indicates that there is a mapping issue related to renaming material numbers during a data migration or conversion process. This error typically arises in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other conversion tools.
Cause: The error occurs when the system attempts to rename material numbers, but there is no mapping defined for the old material number to the new material number. This can happen due to several reasons: Missing Mapping Entries: The mapping table that should contain the old and new material numbers is incomplete or missing entries. Incorrect Configuration: The configuration settings for the migration process may not have been set up correctly, leading to the absence of necessary mappings. Data Integrity Issues: There may be issues with the source data that prevent the system from correctly identifying the material numbers that need to be renamed.
Solution: To resolve the error CNV_20700019,
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