How To Fix CNV_INDX251 - Unknown structure variant(s) reported in &1 (&2 times); see link.

CNV_INDX251 - Overview

• Message type: E = Error

• Message class: CNV_INDX - Messages for conversion of INDX-like tables

• Message number: 251

• Message text: Unknown structure variant(s) reported in &1 (&2 times); see link.

What causes this issue?

Unknown structure variant was reported in &V1& &V2& times.

System Response

If the structure variant is unknown the data cannot be read and written
correctly.
The conversion is not possible.
The status is set to 'Error'.

How to fix this error?

You can use the troubleshooting activity to resolve the error.
Note that the resolution in this case ignoring of specific data entries.
If the data entry should not be ignored or if you are not sure whether
it can be ignored then the actual solution for the error should be
provided.
If the error occured within the data created by SAP standard application
contact SAP for support.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

CNV_INDX251 - Details

• The SAP error message CNV_INDX251 typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that there are unknown structure variants in the data being processed, which means that the system has encountered data structures that it does not recognize or that are not defined in the expected format.
  
  Cause:
  
  Missing Structure Definitions: The structure variants that the system is trying to process are not defined in the system. This can happen if the data model has changed or if the migration tool is not updated to recognize new structures.
  Incorrect Data Mapping: The data being migrated may not match the expected format or structure defined in the target system.
  Version Mismatch: There may be a version mismatch between the source and target systems, leading to discrepancies in the expected data structures.
  Custom Developments: If there are custom fields or structures