Message type: E = Error
Message class:  CNV_40305 - Asset transfer postings due to a change of account determ. 
Message number: 071
Message text: Check posting key for required fields
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The SAP error message CNV_40305071 typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that there is an issue with the posting key configuration, specifically that required fields for the posting key are not filled in correctly.
Cause: Missing Required Fields: The error usually arises when mandatory fields associated with a specific posting key are not populated in the data being processed. Incorrect Posting Key: The posting key used may not be appropriate for the type of transaction being processed.
Configuration Issues: There may be configuration issues in the SAP system regarding the posting keys, such as missing or incorrect settings in the Financial Accounting (FI) module.
Solution: Check Required Fields: Review the data being uploaded or migrated to ensure that all required fields for the specified posting key are filled in. This includes fields like account numbers, amounts, and any other mandatory
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