Material Ledger must be set productive for valuation area &

Scenario 1: New valuation area has been created in S/4HANA system
- It is required to activate Material Ledger via transactions OMX2, OMX3
and OMX1.
- Afterwards, it needs to be set productive via transaction CKMSTART.

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

Scenario 2: System conversion from SAP ERP Business Suite or SAP Simple
Finance to S/4HANA and valuation area has already existed in migration
source system
- Please stick to the process described in SAP note 2352383.
Scenario 3: Valuation area &1 is blocked for any ML related action
Company code is blocked for any Material Ledger related actions due to
open Q to P transport. Scenarios like material creation or material
posting are not possible.
See note 2831274 for more information.

Error message extract from SAP system. Copyright SAP SE.