Message type: E = Error
Message class:  CNV_MBT_09_A - Message class for drop-solution 
Message number: 018
Message text: Sender not defined for this package.
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The SAP error message CNV_MBT_09_A018 indicates that there is an issue with the configuration of the sender for a specific package in the context of a data migration or conversion process. This error typically arises during the execution of a migration project, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error message "Sender not defined for this package" usually occurs due to one of the following reasons: Missing Configuration: The sender (source system or data source) has not been properly defined or configured in the migration settings for the specific package you are trying to use. Incorrect Package Assignment: The package you are trying to execute may not be correctly assigned to a sender, or the sender may not be active or available. Data Migration Cockpit Issues: There may be issues with the Data Migration Cockpit setup, such as missing or incorrect entries in the relevant tables.
Solution: To resolve the error,
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