Message type: E = Error
Message class:  CNV20400 - Message class CNV20400 
Message number: 209
Message text: Table &1 is set to NOTUSE=' ' for the merge
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The SAP error message CNV20400209 indicates that a specific table (denoted as &1 in the message) is set to NOTUSE=' ' during a merge operation in a data migration or conversion process. This typically occurs in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other data conversion scenarios.
Cause: The error arises when the system attempts to merge data from a source table into a target table, but the target table is marked as "not in use" (i.e., NOTUSE is set to a blank value). This means that the table is either not intended to be part of the merge process or is excluded from the data migration due to configuration settings.
Solution: To resolve this error, you can take the following steps: Check Table Configuration: Review the configuration settings for the table in question. Ensure that the table is intended to be included in the merge process. If
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