Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 678
Message text: Account &1 in the mapping for CoA &2 does not exist in CoA &2
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The SAP error message CNV_20100678 indicates that there is an issue with the mapping of accounts during a conversion process, specifically when dealing with Chart of Accounts (CoA) in SAP. The error message states that the account specified (represented by &1) in the mapping for the Chart of Accounts (CoA) specified (represented by &2) does not exist in the target Chart of Accounts (also represented by &2).
Cause: Missing Account: The account you are trying to map does not exist in the target Chart of Accounts. This could be due to a typo, or the account may not have been created in the target system. Incorrect Mapping: The mapping configuration may be incorrect, leading to an attempt to map an account that is not valid in the target CoA. Data Migration Issues: If this error occurs during a data migration process, it may indicate that the source data has accounts that were not properly
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