If this scenario occurs, click on the generated ‘Run ID’ in the ‘Last Executions’ table. The reason for the test failing to be assigned to the manual testers and having the ‘Not Executed’ status should be detailed in the ‘Results’ page.
The only reason manual tests should automatically be assigned the status of ‘Not Executed’ is because of a lack of Manual Testing Client licenses available. The warning message should state
Failed to initialize execution because a licensing error occurred (SilkMeter response: Obtaining "SilkCentralManualTestingClient 9.0" license for user "username" from SilkMeter failed -  All licenses are in use).
Note that each user currently assigned manual tests, that are pending execution, will be using a Manual Testing Client licenses.