Message type: E = Error
Message class:  CNV_NCE_BAS - Number conversion engine: messages 
Message number: 123
Message text: Changes detected in table NRIV, initialization of mappings is required
The system has detected that table NRIV have been changed since the
activity <ZK>Initialize Mapping Values for Number Range Objects</> was
executed (for example new number range intervals have been created or
existing number range intervals have been changed). This means that
information about number range intervals of the corresponding number
range object is not up to date.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Execute the activity <ZK>Initialize Mapping Values for Number Range
Objects</> again. The system updates all changed number range objects.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message CNV_NCE_BAS123 indicates that changes have been detected in the table NRIV, which is related to number range intervals. This error typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools.
Cause: The error arises when the system detects that the number range intervals (stored in the NRIV table) have been modified after the initial mapping or conversion process was set up. This can happen due to: Changes in Number Ranges: If number ranges have been added, deleted, or modified in the NRIV table after the initial mapping was created. Concurrent Changes: Other processes or users may have made changes to the number ranges while the migration or conversion process was ongoing. Inconsistent Data: The data in the NRIV table may not match the expected state for the migration process.
Solution: To resolve this error, you will need to reinitialize the mappings for
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