Message type: E = Error
Message class:  CNV_10020 - Message class for package 10020 
Message number: 457
Message text: Function module &1 has already been turned into coding again
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message CNV_10020457, which states "Function module &1 has already been turned into coding again," typically occurs during the conversion or migration processes in SAP systems, particularly when using the SAP Conversion Tools or during system upgrades.
Cause: This error usually indicates that there is an attempt to reprocess or re-activate a function module that has already been processed. This can happen due to: Duplicate Processing: The function module has already been converted or activated, and the system is trying to do it again. Inconsistent State: The system might be in an inconsistent state where it thinks the function module needs to be processed again.
Configuration Issues: There may be issues with the configuration or setup of the conversion tools or the migration process.
Solution: To resolve this error, you can take the following steps: Check the Status: Verify the status of the function module in question. You can do this by checking the transaction SE37
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