Message type: E = Error
Message class:  CNV_MBT - PCL message class 
Message number: 342
Message text: Subproject &1 cannot be created under Project &2.
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The SAP error message CNV_MBT342 indicates that there is an issue with creating a subproject under a specified project in the context of a migration or conversion project. This error typically arises in the SAP Landscape Transformation (SLT) or during data migration processes.
Cause: The error message CNV_MBT342 can be caused by several factors, including: Project Status: The main project (Project &2) may not be in a status that allows the creation of subprojects. For example, if the main project is locked or in a completed state, you may not be able to create new subprojects. Authorization Issues: The user attempting to create the subproject may not have the necessary authorizations or roles assigned to perform this action.
Configuration Issues: There may be configuration settings in the project management or migration tools that prevent the creation of subprojects. Technical Limitations: There could be technical limitations or restrictions in the system that prevent the creation of subprojects
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