Message type: E = Error
Message class:  CNV_MBT - PCL message class 
Message number: 003
Message text: You are not authorized to carry out this task
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_MBT003, which states "You are not authorized to carry out this task," typically indicates that the user attempting to perform a specific action does not have the necessary authorizations or permissions in the SAP system. This error is often encountered during data migration or conversion tasks, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. Causes: Insufficient Authorizations: The user lacks the required roles or authorizations to execute the task. Role Assignment Issues: The roles assigned to the user may not include the necessary transaction codes or authorization objects. Profile Issues: The user profile may not be correctly configured to allow access to the required functions. System Configuration: There may be specific configurations or restrictions in place that limit user access to certain tasks. Solutions: Check User Roles: Verify the roles assigned to the user in transaction SU01 (User Maintenance). Ensure that the user has the necessary roles that include the required authorizations
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