Windows 7 Task Scheduler

I scheduled a task and now I want to delete it but I don’t see it in the task list. When I try to create another task with the same name, it says this task already exists. Where can I find this task and how can I delete it?

If this is of any help

maybe as a checklist - should be a straight-forward procedure
http://windows.microsoft.com/en-US/windows7/schedule-a-task

and a complete guide from TinyHacker
http://tinyhacker.com/hacks/complete-guide-to-windows-7s-task-scheduler/