Message type: E = Error
Message class:  CNV_CMIS_A_20 - Message class for Cross-Client Customizing Comparison (SLO) 
Message number: 079
Message text: Upload from File option is not available with Complete Selection.
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The SAP error message CNV_CMIS_A_20079 indicates that the "Upload from File" option is not available when using the "Complete Selection" mode in the context of a data migration or conversion process, typically associated with the SAP Conversion Management Information System (CMIS).
Cause: This error usually occurs due to the following reasons: Selection Mode: The "Complete Selection" mode is designed to process all data in a specific way, and it may not support file uploads as a method of data input. Configuration Settings: The system may be configured in such a way that it restricts the use of file uploads in certain selection modes. Data Migration Process: The specific data migration or conversion process you are using may not allow for file uploads when a complete selection is being made.
Solution: To resolve this error, consider the following solutions: Change Selection Mode: If possible, switch from "Complete Selection" to a mode that allows for file uploads, such as "Partial
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