Message type: E = Error
Message class:  CNV_PE - General messages for posting engine 
Message number: 501
Message text: Undo transfer method &1 is not assigned to transfer method &2
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The SAP error message CNV_PE501 indicates that there is an issue with the assignment of transfer methods in the context of a data migration or conversion process. Specifically, the error states that the "Undo transfer method &1 is not assigned to transfer method &2." This typically occurs in scenarios involving the SAP Data Migration Cockpit or similar tools where data is being transferred from one system to another.
Cause: Misconfiguration: The transfer method that is supposed to handle the undo operation is not properly configured or assigned in the system. Missing Assignment: The specific undo transfer method (denoted as &1) has not been linked to the main transfer method (denoted as &2) in the configuration settings. Data Migration Settings: There may be inconsistencies in the data migration settings or profiles that are being used.
Solution: Check Transfer Method Configuration: Go to the relevant configuration settings in the SAP system where transfer methods are defined. Ensure that the undo
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