In attached word Doc u can see the details select on the task and there is a delete option on the right side. Dont select the job directly but select the line of the job.
The user interface can sometimes be a little bit confusing. Just click on "Job Management" on the right of QlikView Publisher Control Panel in your browser. Then click on a job, it should turn green. After this you can click on "Delete Selected Job" in the Job Actions menu on the right.
Same for tasks, source documents, etc.