Message type: E = Error
Message class:  CNV_OM_PRESEL - Messages for LT Object Based Preselection 
Message number: 139
Message text: The following tasks have been selected to be started
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The SAP error message CNV_OM_PRESEL139 typically occurs during the execution of a conversion or migration project, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that there are tasks that have been selected for processing, but there may be issues with the selection or configuration of those tasks.
Cause: Task Selection Issues: The error may arise if there are inconsistencies or conflicts in the selected tasks for the migration or conversion process. Configuration Errors: Incorrect configuration settings in the migration cockpit or related tools can lead to this error. Missing Dependencies: Some tasks may depend on others, and if those dependencies are not met, it can trigger this error. Authorization Issues: Lack of proper authorizations for executing certain tasks can also lead to this error message.
Solution: Review Task Selection: Go through the selected tasks and ensure that they are appropriate for the migration or conversion process. Deselect any tasks that are
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