Message type: E = Error
Message class:  CNV_MBT_46 - PCL message class 
Message number: 218
Message text: Source activity is not valid; select an activity from pull down list
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The SAP error message CNV_MBT_46218 indicates that the source activity you are trying to select is not valid in the context of the Migration Object you are working with. This error typically occurs during data migration processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: Invalid Selection: The source activity you are trying to select may not be available for the specific migration object you are working on.
Configuration Issues: There may be configuration issues in the migration project that prevent the selection of valid activities. Authorization Issues: The user may not have the necessary authorizations to access certain activities. Data Consistency: The data or settings in the migration cockpit may not be consistent, leading to the unavailability of certain activities.
Solution: Select from the Dropdown: Ensure that you are selecting an activity from the provided dropdown list. If the desired activity is not listed, it may not be applicable for the current
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