Message type: E = Error
Message class:  CNV_DMC_SIN - Messages for s-innovations migration 
Message number: 378
Message text: Company code and WHT type cannot be initial in &1, withh. tax code is &2
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The SAP error message CNV_DMC_SIN378 indicates that there is an issue with the configuration of withholding tax (WHT) in the context of a company code. Specifically, the error states that the company code and withholding tax type cannot be initial (i.e., they cannot be empty) for the specified transaction or context.
Cause: Missing Configuration: The company code or withholding tax type is not properly configured in the system. This could happen if the necessary settings for withholding tax have not been maintained in the relevant configuration tables. Data Entry Error: There may be a data entry error where the company code or withholding tax type has not been filled in correctly in the transaction. Migration Issues: If this error occurs during a data migration process (e.g., using the SAP Data Migration Cockpit), it could be due to missing or incorrect data in the source system.
Solution: Check Configuration: Go to the SAP configuration settings for withholding tax
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