Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 204
Message text: Cntry-spec. CoA &3 (to be implemented) is also target for a conversion
You are going to implement the country-specific chart of accounts &V3&
for target chart of accounts &V2& (mapping &V1& -> &V2&).
The system found that chart of accounts &V3& was specified as the target
chart of accounts in a mapping entry.
It is not allowed to implement a chart of accounts as country-specific
chart of accounts and use this same chart of accounts as a target chart
of accounts.
Either change the mapping table so that country-specific chart of
accounts &V3& is not used as target chart of accounts in a mapping
entry, or do not implement the chart of accounts as a country-specific
chart of accounts.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message CNV_20100204 typically relates to issues encountered during the data migration or conversion process, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This specific error indicates that there is a country-specific Chart of Accounts (CoA) that is marked for conversion but has not been implemented in the target system.
Cause: Missing Implementation: The country-specific Chart of Accounts (CoA) that is referenced in the error message has not been implemented in the target system. This could happen if the CoA is not part of the configuration or if it has not been activated.
Configuration Issues: There may be configuration issues in the source or target system that prevent the proper mapping or conversion of the CoA. Data Migration Settings: The settings in the data migration tool may not be correctly configured to handle the specific CoA for the country in question.
Solution: Implement the CoA: Ensure that the country-specific Chart of
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