Edit the Task
4. Try It: Edit the Task
Enter the Subject: 1 Request new photos

And Try This: Show More Details
Select the Due date: Fri 8/15/2014.
Select the Start date: Fri 8/1/2014.
Change the Status: In progress.
Select a Reminder: Mon Fri 8/8/2014.

What Did That Do? Tasks are often date driven. You may have to finish your Task so that another person can begin their Task.

In this example the Reminder is scheduled one week after the Start date. If you do not begin on the Start date, Outlook will prompt you again! Keep going...

Tasks->New Task->Show More Details