Message type: E = Error
Message class:  CNV_20200_CHECK - Messages for check functions (company code merge) 
Message number: 407
Message text: The existing mapping seems no longer to be valid. See longtext!
The cash journal business transaction mapping is automatically generated
based on a given company code (merge) mapping.
It was determined that the existing cash journal business transaction
mapping is no longer valid according to the current existing company
code mapping.
It seems that a change in the company code mapping or a change in the
existing cash journal business transaction customizing (transaction
FBCJC2) was done.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Re-execute activity <ZK>Check Whether Merge Affects Cash Journal
Business Transact.</> and check the mapping values for the cash journal
business transactions.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message CNV_20200_CHECK407 indicates that there is an issue with the mapping configuration in a data migration or conversion process. This error typically arises during the execution of a data migration project, particularly when using SAP's Conversion Tools or the SAP S/4HANA Migration Cockpit.
Cause: Invalid Mapping: The mapping between source and target data structures may have been altered or is no longer valid. This can happen if there have been changes in the data model, such as changes in field names, data types, or structures in the source or target systems.
Configuration Issues: The mapping configuration might not have been set up correctly, or there may be missing entries in the mapping tables. Data Integrity Issues: The data in the source system may not conform to the expected format or constraints defined in the target system, leading to mapping failures.
Solution: Review Mapping Configuration: Check the mapping configuration in the migration tool. Ensure
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