Message type: E = Error
Message class:  CNV_20200_CHECK - Messages for check functions (company code merge) 
Message number: 156
Message text: FI-SL ledger &1 does not occur in all participating company codes
FI-SL ledger &V1& does not occur in all participating company codes.
Error
A company code merge will result in inconsistencies on special ledger
level. A company code merge can be done only when all participating
company codes have the same settings. We recommend that you contact your
special ledger consultant in order to identify additional activities.
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_20200_CHECK156 indicates that there is an inconsistency in the configuration of the Financial Accounting (FI) Subledger (FI-SL) ledgers across different company codes. Specifically, it means that the specified ledger (denoted as &1 in the error message) is not consistently defined across all the company codes that are participating in the conversion or migration process.
Cause: Inconsistent Ledger Configuration: The specified FI-SL ledger is not activated or configured for all the company codes involved in the process. This can happen if some company codes have the ledger defined while others do not. Data Migration Issues: During data migration or conversion processes, if the ledgers are not uniformly set up across all company codes, this error can occur. Customizations: Custom configurations or changes in the system that affect the ledger settings may lead to this inconsistency.
Solution: Check Ledger Configuration: Go to the configuration settings in SAP and verify the ledger settings for each company
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