Message type: E = Error
Message class:  CNV_MBT - PCL message class 
Message number: 853
Message text: User &1 is not assigned to subproject &2 .
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The SAP error message CNV_MBT853 indicates that a user is not assigned to a specific subproject within a project. This error typically arises in the context of data migration or project management within SAP systems, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error occurs when: A user attempts to access or perform actions related to a subproject for which they do not have the necessary authorization or assignment. The user may not be included in the user assignments for the specific subproject in the project management or migration settings.
Solution: To resolve this error, you can take the following steps: Check User Assignment: Go to the project management or migration cockpit settings. Verify if the user (User ID &1) is assigned to the subproject (Subproject ID &2) in question. Assign User to Subproject: If the user is not assigned, you will need to add them to the subproject. This can typically be done by: Navigating to
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