Message type: E = Error
Message class:  CNV_OM_PRESEL - Messages for LT Object Based Preselection 
Message number: 042
Message text: Some preselection tasks are not on status "ready"
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The SAP error message CNV_OM_PRESEL042 indicates that some preselection tasks in the conversion process are not in the "ready" status. This typically occurs during data migration or conversion activities, particularly when using SAP's Conversion Tools or the SAP S/4HANA Migration Cockpit.
Cause: The error can be caused by several factors, including: Incomplete Preselection Tasks: Some preselection tasks may not have been completed successfully, leading to them not being marked as "ready." Errors in Previous Steps: If there were errors in earlier steps of the migration process, it could prevent subsequent tasks from being marked as ready.
Configuration Issues: Incorrect configuration settings or missing prerequisites for the preselection tasks can lead to this error. Data Issues: Problems with the data being migrated, such as inconsistencies or missing data, can also cause preselection tasks to fail.
Solution: To resolve the error, you can follow these steps: Check Task Status: Go to the relevant transaction (e.g., transaction code LTMC for Migration Cockpit)
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