Message type: E = Error
Message class:  CNV_10020 - Message class for package 10020 
Message number: 377
Message text: Filling method 3 is not possible with execution in test mode
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The SAP error message CNV_10020377 indicates that a specific filling method (in this case, filling method 3) cannot be executed in test mode. This error typically arises during data migration or conversion processes, particularly when using SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other conversion tools.
Cause: The error occurs because filling method 3 is designed to perform actions that are not permitted in test mode. Test mode is generally used to simulate the execution of a process without making any actual changes to the database. Filling method 3 may involve operations that require actual data manipulation or changes that cannot be validated in a non-destructive manner.
Solution: To resolve this error, you can take the following steps: Switch to Production Mode: If you are running the migration or conversion in test mode, switch to production mode (or execution mode) to allow the filling method to proceed. This will enable
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