Message type: E = Error
Message class:  CNV_NCE_BAS - Number conversion engine: messages 
Message number: 209
Message text: Execution is permitted only in a control system
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The SAP error message CNV_NCE_BAS209 indicates that a certain operation or transaction is being attempted in a non-control system environment, which is not permitted. This error typically arises in the context of SAP system conversions or migrations, particularly when using the SAP S/4HANA Migration Cockpit or other conversion tools.
Cause: The error occurs because the operation you are trying to perform is restricted to a control system. A control system is typically a designated system that manages and oversees the migration or conversion process, ensuring that all necessary checks and balances are in place. If you attempt to execute the operation in a non-control system (like a development or quality assurance system), the system will throw this error.
Solution: To resolve this error, you should: Identify the Control System: Determine which system is designated as the control system for your migration or conversion project. This is usually specified in the project documentation or by your
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