Hi noelpd,
I know it’s late and you might have resolved your problem, but I have come up with a cause and solution (at least in my case).
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[]In order to schedule tasks, whatever it is the task, you must assign an image to the host/group you are trying to send the task.
[]The server from which you are sending the task must be the group’s master node. I realised that, in WebUI > Other Information > Log Viewer > Scheduler, the server wasn’t the group manager and it wasn’t scheduling tasks.
[/LIST]
I hope this helps.