Message type: E = Error
Message class:  CNV_MBT_DEX - DMIS Data Extract related messages 
Message number: 201
Message text: Invalid Call of function module &
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The SAP error message CNV_MBT_DEX201 Invalid Call of function module & typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that there is an issue with the function module being called, which may not be available, incorrectly configured, or not suitable for the current context. Causes: Function Module Not Found: The specified function module may not exist in the system or may not be activated. Incorrect Parameters: The parameters being passed to the function module may be incorrect or not matching the expected format. Authorization Issues: The user executing the migration may not have the necessary authorizations to call the function module. System Configuration: There may be issues with the system configuration or the specific migration scenario being used. Version Compatibility: The function module may not be compatible with the version of SAP you are using. Solutions: Check Function Module: Verify that the
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