Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 644
Message text: No duplicate COES table keys during conversion; no adjustment required
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The SAP error message CNV_20100644 indicates that during a data conversion process, the system has detected that there are no duplicate keys in the COES (Controlling Object Assignment) table. This message typically arises in the context of data migration or conversion projects, particularly when using SAP's Conversion Tools or the SAP S/4HANA Migration Cockpit.
Cause: The error message suggests that the conversion process is checking for duplicate entries in the COES table, which is used to manage assignments of controlling objects. The absence of duplicates means that the data is already in a consistent state, and therefore, no adjustments or changes are necessary.
Solution: Since the message indicates that there are no duplicates and no adjustments are required, there is typically no action needed on your part. However, if you are expecting duplicates or if this message is unexpected, consider the following steps: Review Data: Check the source data to ensure that it is as
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