Message type: E = Error
Message class:  CNV_PE - General messages for posting engine 
Message number: 821
Message text: Sender processing is excluded
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message CNV_PE821: Sender processing is excluded typically occurs in the context of data migration or conversion processes, particularly when using SAP's tools for data transfer, such as the SAP S/4HANA Migration Cockpit or other data migration solutions.
Cause: The error message indicates that the sender processing for a specific data object or entity has been excluded from the migration process. This can happen for several reasons:
Configuration Issues: The sender object may not be properly configured in the migration settings. Data Mapping: The data mapping for the sender object may not be defined, or it may be set to exclude certain records or fields. Business Rules: There may be business rules or conditions that prevent the processing of certain data entities. Version Compatibility: The version of the migration tool or the source system may not be compatible with the target system.
Solution: To resolve the CNV_PE821 error, you can take the following steps: Check Configuration: Review
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