Message type: E = Error
Message class:  CNV_OM_PRESEL - Messages for LT Object Based Preselection 
Message number: 118
Message text: Table count started as batch job for preselection table &1
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The SAP error message CNV_OM_PRESEL118 typically occurs during the execution of a conversion or migration process, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that the system has started a batch job to count the entries in a preselection table, but there may be issues related to the execution or the data in that table.
Cause: Data Volume: The preselection table may contain a large volume of data, which can lead to performance issues or timeouts during the counting process. Locking Issues: If other processes are accessing the same table, it may lead to locking issues that prevent the batch job from executing properly.
Configuration Issues: There may be misconfigurations in the migration settings or the environment that could lead to this error. Database Performance: The underlying database may be experiencing performance issues, which can affect the execution of batch jobs.
Solution: Check Job Logs: Review the job logs for any
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