Message type: E = Error
Message class:  CNV_MBT_NE - Standard Messages for Notifications 
Message number: 104
Message text: Data Loss Warning
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The SAP error message CNV_MBT_NE104, which indicates a "Data Loss Warning," typically arises during data migration processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This warning suggests that some data may not be transferred correctly or completely, which could lead to data integrity issues in the target system.
Cause: The CNV_MBT_NE104 warning can be triggered by several factors, including: Data Mapping Issues: The source data may not map correctly to the target data structure, leading to potential data loss. Incompatible Data Types: Differences in data types between the source and target systems can cause truncation or loss of data. Missing Required Fields: If required fields in the target system are not populated from the source data, this can lead to incomplete records. Data Transformation Errors: Errors during the transformation of data from the source format to the target format can result in data loss.
Configuration Issues: Incorrect configuration settings in the
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