Message type: E = Error
Message class:  CNV_CDMC_CTS - CDMC Change and Transport System Analysis 
Message number: 021
Message text: Enter a valid input request
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The SAP error message CNV_CDMC_CTS021: Enter a valid input request typically occurs in the context of data migration or conversion processes, particularly when using the SAP Conversion Tools (like the SAP S/4HANA Migration Cockpit or other data migration tools). This error indicates that the system is expecting a valid input request, but the provided input is either missing, incorrect, or not recognized. Causes: Invalid Input Request: The input request you are trying to process may not exist or may have been deleted. Incorrect Format: The input request may not be in the expected format or structure. Authorization Issues: The user may not have the necessary permissions to access or execute the input request. System Configuration: There may be configuration issues in the migration tool or the underlying system that prevent the request from being recognized. Data Consistency Issues: The data being referenced may not be consistent or may have integrity issues. Solutions: Verify Input Request: Check if the
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