Message type: E = Error
Message class:  CNV_20000 - Messages for fiscal year change 
Message number: 145
Message text: Fiscal year variant &1 selected for adjustment of non-leading ledger(s)
Fiscal year variant &V1& is selected for adjustment.
Selected variant is only assigned to company code and non-leading ledger
combination in a system.
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.
The SAP error message CNV_20000145 indicates that there is an issue with the fiscal year variant selected for the adjustment of non-leading ledgers during a data migration or conversion process. This error typically arises in the context of the SAP S/4HANA migration or during the use of the SAP Conversion Tools.
Cause: The error occurs when the fiscal year variant specified for the non-leading ledger does not match the fiscal year variant of the leading ledger or is not properly configured. This can happen due to: Mismatch in Fiscal Year Variants: The fiscal year variant assigned to the non-leading ledger is different from that of the leading ledger.
Configuration Issues: The fiscal year variant may not be correctly set up in the system for the non-leading ledger. Data Migration Settings: Incorrect settings in the migration tool or process that do not align the fiscal year variants properly.
Solution: To resolve this error, you can take the following
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