Message type: E = Error
Message class:  CNV_DMC_SIN - Messages for s-innovations migration 
Message number: 141
Message text: Document Type cannot be initial in the conversion rule &1, Doc.Type is &2
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The SAP error message CNV_DMC_SIN141 indicates that there is an issue with the document type in a conversion rule during a data migration or conversion process. Specifically, the error states that the document type cannot be initialized in the specified conversion rule.
Cause: Invalid Document Type: The document type specified in the conversion rule may not be valid or recognized by the system.
Configuration Issues: There may be configuration issues in the system that prevent the document type from being initialized. Data Mapping Errors: The mapping of the document type in the conversion rules may not be set up correctly, leading to this error. Missing Authorizations: The user executing the conversion may not have the necessary authorizations to work with the specified document type.
Solution: Check Document Type: Verify that the document type specified in the conversion rule is valid and exists in the system. You can do this by checking the configuration settings for document types
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