You cann't run a task at the user level in w7 unless that user is logged on.
In windows 8.1/ 10 or server12r2 you could use an 'Enhanced session' to remotely run a task without the user being logged in, assuming you have set the hyper-v hypervisor to allow that and have admin rights but I'm not sure if that helps because you havn't told us why you need to do this or what the task is.