I create a user called Task Scheduler (this way if a real user's sign on is deleted, your tasks will still work). Be sure this Task Scheduler user has all the needed rights.
I sign onto the server as administrator and set up the task from there. Be sure there is a printer set up on the server. I instruct the users that if they need to modify the task, go into the server as administrator. It's been awhile since setting this up, but I have had some success, after pulling my hair out.