Message type: E = Error
Message class:  CNV_10020 - Message class for package 10020 
Message number: 145
Message text: &1 &2: Conc./frag. source object &3 does not exist
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The SAP error message CNV_10020145 typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. The error message indicates that a specified source object (like a table or a field) does not exist in the system.
Cause: Non-existent Source Object: The error suggests that the source object (e.g., a table, field, or structure) referenced in the migration process is not found in the system. This could be due to: The object was deleted or not created. There is a typo in the object name. The object is part of a different system or client. The object is not activated or not available in the current context.
Configuration Issues: Sometimes, the configuration settings for the migration might not be set up correctly, leading to references to non-existent objects. Version Mismatch: If you are migrating from an older version of SAP to a newer one, there may be changes
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