Message type: E = Error
Message class:  CNV_CMIS_G - CMIS: general messages 
Message number: 021
Message text: - A buffer extraction has to be performed
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The SAP error message CNV_CMIS_G021 - "A buffer extraction has to be performed" typically occurs in the context of data migration or conversion processes, particularly when using the SAP Conversion Management Information System (CMIS) or during the execution of a data migration project.
Cause: This error indicates that the system requires a buffer extraction to be performed before proceeding with the current operation. Buffer extraction is a process where data is temporarily stored in a buffer to facilitate efficient processing and migration. The error may arise due to: Incomplete Data Preparation: The necessary data has not been extracted or prepared in the buffer.
Configuration Issues: There may be misconfigurations in the migration settings or parameters. Previous Steps Not Completed: The migration process may have previous steps that need to be completed before the current step can be executed.
Solution: To resolve the CNV_CMIS_G021 error, you can follow these steps: Perform Buffer Extraction: Navigate to the relevant transaction or program
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