Message type: E = Error
Message class:  CNVMBTSCRAMBLE - Scramble 
Message number: 015
Message text: Please select a secondary field line
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
Unfortunately, there isn't any extra information in this error notice.
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The SAP error message CNVMBTSCRAMBLE015 typically occurs in the context of data migration or transformation processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that the system requires the user to select a secondary field line, which is necessary for the operation being performed.
Cause: The error is usually caused by one of the following reasons: Missing Selection: The user has not selected a secondary field line that is required for the data transformation or migration process.
Configuration Issues: There may be a configuration issue in the migration cockpit or the data mapping settings that does not allow the selection of the necessary secondary field. Data Structure: The data structure being processed may require additional fields to be specified, which have not been provided.
Solution: To resolve the error, you can follow these steps: Select a Secondary Field: Go back to the screen where the error occurred and ensure that you select the
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