Message type: E = Error
Message class:  CNV_NCE_BAS - Number conversion engine: messages 
Message number: 212
Message text: Execution in a display mode (not a control system)
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The SAP error message CNV_NCE_BAS212 typically indicates that a certain operation or transaction is being attempted in a display mode rather than in a control or edit mode. This error is often encountered in the context of data migration or conversion processes, particularly when using SAP's tools for data conversion (like the SAP S/4HANA Migration Cockpit or other data migration tools).
Cause: The error occurs when: The system is in a display mode, which restricts the ability to perform certain actions that require editing or control capabilities. The user may not have the necessary authorizations to switch to a mode that allows for the required operations. The transaction or program being executed is not designed to run in display mode.
Solution: To resolve the CNV_NCE_BAS212 error, consider the following steps: Check Transaction Mode: Ensure that you are executing the transaction in the correct mode. If you are in display mode, switch to the appropriate mode (usually edit or control
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