Message type: E = Error
Message class:  CNV_20211_CHECK - Messages for check functions (company conversion) 
Message number: 012
Message text: All participating companies have same local currency &
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The SAP error message CNV_20211_CHECK012 typically occurs during the data migration process, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that all participating companies (or company codes) in the migration process have the same local currency, which is not allowed for the specific operation you are trying to perform.
Cause: The error arises when: You are trying to migrate data for multiple company codes that share the same local currency. The migration process expects different local currencies for the participating entities, which is a requirement for certain types of financial data processing or reporting.
Solution: To resolve this error, consider the following steps: Check Company Code Configuration: Verify the local currency settings for each company code involved in the migration. Ensure that they are configured correctly in the system. Adjust Migration Settings: If the migration process requires different local currencies, you may need to adjust the settings or the data being migrated
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