Message type: E = Error
Message class:  CNVMBT - Messages for MBT/API/PCL 
Message number: 008
Message text: Receiver structure &1 has no sender structure assigned
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The SAP error message CNVMBT008 indicates that there is a problem with the mapping of data structures in a migration or data transfer process. Specifically, it means that the receiver structure (the target structure where data is supposed to be sent) does not have a corresponding sender structure (the source structure from which data is being sent) assigned to it.
Cause: Missing Assignment: The most common cause is that the configuration for the data migration or transfer process is incomplete. The receiver structure has not been linked to a sender structure in the mapping configuration. Incorrect Configuration: There may be an error in the configuration settings where the sender and receiver structures are defined. Data Model Changes: Changes in the data model (e.g., changes in the source or target systems) may have led to the removal or alteration of the expected structures.
Solution: Check Mapping Configuration: Go to the relevant transaction or tool where the mapping is
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