Message type: E = Error
Message class:  CNV_OM - Messages for Objectbased Migration 
Message number: 040
Message text: Creating preselection tasks
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The SAP error message CNV_OM040 typically occurs during the execution of a data migration or conversion process, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error is related to the creation of preselection tasks, which are necessary for the data migration process.
Cause: The error CNV_OM040 can be caused by several factors, including: Missing Configuration: Required configuration settings for the migration project may be missing or incorrectly set up. Data Issues: The source data may have inconsistencies or issues that prevent the creation of preselection tasks. Authorization Issues: The user executing the migration may not have the necessary authorizations to create preselection tasks. Technical Issues: There may be technical issues with the SAP system, such as missing transport requests or incorrect system settings.
Solution: To resolve the CNV_OM040 error, you can take the following steps: Check Configuration: Ensure that all necessary configuration settings for the migration project are correctly set up. This includes checking the migration
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