Message type: E = Error
Message class:  CNV_10020 - Message class for package 10020 
Message number: 257
Message text: Selected DTFLD entries get different package numbers
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The SAP error message CNV_10020257 indicates that there is a discrepancy in the package numbers for selected DTFLD (Data Transfer Field) entries during a data migration or conversion process. This error typically arises in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other data transfer processes.
Cause: The error occurs when the system detects that the selected entries for a particular data transfer field (DTFLD) have been assigned different package numbers. This can happen due to several reasons: Inconsistent Data Preparation: The data being prepared for migration may have been incorrectly segmented or grouped, leading to different package assignments. Manual Changes: If there were manual adjustments made to the data or the migration settings, it could result in inconsistencies.
Configuration Issues: There may be issues with the configuration of the migration tool or the data transfer settings that lead to this error.
Solution: To resolve the error CNV_10020257, you can
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