Message type: E = Error
Message class:  CNV_10020 - Message class for package 10020 
Message number: 665
Message text: &1 &2: Specific function module was not maintained
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The SAP error message CNV_10020665 typically indicates that a specific function module required for a certain operation or process has not been maintained or is missing. This error is often encountered during data migration or conversion processes, particularly when using SAP's data migration tools.
Cause: Missing Function Module: The function module that is supposed to handle a specific task is not available in the system. Incorrect Configuration: The function module may exist but is not properly configured or activated. Version Mismatch: The function module may not be compatible with the version of SAP you are using. Transport Issues: The function module may not have been transported correctly from the development environment to the production environment.
Solution: Check Function Module: Verify if the function module mentioned in the error message exists in the system. You can do this by using transaction code SE37 (Function Builder) and searching for the function module. Maintain Function Module: If the function module is
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