Message type: E = Error
Message class:  CNV_20200_CHECK - Messages for check functions (company code merge) 
Message number: 278
Message text: Company code missing for source house bank ID &1
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The SAP error message CNV_20200_CHECK278 indicates that there is a missing company code for a specified source house bank ID. This error typically arises during data migration or conversion processes, particularly when using SAP's Conversion Tools or during the implementation of SAP S/4HANA.
Cause: The error occurs when the system is unable to find a valid company code associated with the specified house bank ID. This can happen due to several reasons:
Configuration Issues: The house bank may not be properly configured in the system. Missing Data: The company code may not be assigned to the house bank in the configuration settings. Data Migration Errors: During data migration, the mapping between house banks and company codes may not have been established correctly.
Solution: To resolve this error, you can follow these steps: Check House Bank Configuration: Go to the transaction code FI12 (House Bank) in SAP. Verify that the house bank ID in question is correctly configured. Ensure that the house
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