Message type: E = Error
Message class:  CNV_10520 - Conversion module of FI-CA FIKEY-logic 
Message number: 040
Message text: Module/method &2 returned error: &1; contact SAP for support
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_10520040 typically indicates an issue encountered during a data migration or conversion process, particularly when using SAP's tools for data migration (like the SAP S/4HANA Migration Cockpit or other data conversion tools). The error message suggests that a specific module or method has returned an error, and it advises contacting SAP support for further assistance. Possible Causes: Data Quality Issues: The data being migrated may not meet the required format or constraints, leading to validation errors. Configuration Problems: Incorrect configuration settings in the migration tool or in the target system can cause errors during the migration process. Missing Dependencies: Required objects, such as tables or fields, may be missing in the target system. Authorization Issues: The user executing the migration may not have the necessary authorizations to perform certain actions. Technical Errors: There may be bugs or issues in the migration tool itself or in the underlying SAP system. Solutions: Check Logs: Review the
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