Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 631
Message text: Account/cost element &1 &2 is not target acct/CostEl for the conversion
The system found that according to the mapping table account (cost
element) &V1& &V2& is no target account (cost element).
In this case, you will not be allowed to enter any names for it. This is
necessary to ensure that no names are changed or created incorrectly
(for example in a chart of accounts that does not participate in the
conversion).
Check your entries.
&ADDITIONAL_HINTS&
If account &V2& exists in the source chart of accounts and will only be
transferred implicitly into target chart of accounts &V1& (by changing
the chart of accounts ID), add the following entry in the mapping: &V2&
--> &V2&
Having included this mapping entry, you can maintain names for target
account &V1& &V2&.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message CNV_20100631 indicates that there is an issue with the account or cost element mapping during a data conversion process, typically in the context of a migration or data transfer project. This error suggests that the specified account or cost element does not match the expected target account or cost element for the conversion.
Cause: Mapping Issues: The account or cost element specified in the conversion does not exist in the target system or is not correctly mapped. Configuration Errors: There may be configuration issues in the mapping tables that define how source accounts/cost elements relate to target accounts/cost elements. Data Integrity Issues: The source data may contain invalid or unexpected values that do not correspond to the target system's structure. Missing Entries: The target account or cost element may not have been created or activated in the target system.
Solution: Check Mapping Configuration: Review the mapping configuration for the conversion process. Ensure that the
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