Message type: E = Error
Message class:  CNV_20200_CHECK - Messages for check functions (company code merge) 
Message number: 012
Message text: Company code &1 with valuation area &2; material ledger activated = &3
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The SAP error message CNV_20200_CHECK012 typically relates to issues with the configuration of the material ledger in the context of a company code and valuation area. This error is often encountered during data migration or system conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error message indicates that there is a mismatch or inconsistency regarding the activation of the material ledger for a specific company code and valuation area. The message provides the following details: Company Code (&1): The specific company code being referenced. Valuation Area (&2): The valuation area associated with the company code. Material Ledger Activated (&3): Indicates whether the material ledger is activated (usually "X" for activated and blank for not activated). The error can occur due to: The material ledger being activated for a valuation area that is not consistent with the settings in the company code. The material ledger being deactivated when it should be activated,
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