Maintaining a Personal Task List
In Outlook, tasks are essentially to-do items. They can be as simple as a note to yourself ("Pick up milk on the way home") or you can add start dates, due dates, and detailed notes, and then track your progress on a complex task over time. Outlook lets you define one-time tasks or recurring tasks, such as weekly status reports. A list of current tasks appears on the Outlook Today page.
→ To learn how you can modify the Outlook Today page to meet your needs, see "Customizing the Outlook Today Page".
Entering Tasks
The absolute simplest way to create a task is to view the Tasks folder in Simple List view. To do so, click where you see the gray letters Click Here to Add a New Task, press Tab, enter a due date, and then press Enter to record the task.
To create a new task with more details, choose File, New, Task or press Ctrl+Shift+K. In the Task form (see Figure 11.13), enter the task text in the Subject box and fill in any of the additional fields, all of which are optional.
Figure 11.13. The only required field for a Task item is the Subject line; enter date and status information if you plan to produce status reports.
Enter the Due Date first, and then fill in the Start Date. Fill in the Status, Priority, and % Complete boxes only if you want to be able to sort a complex list of tasks using this information. By default, Outlook creates a reminder for every task on its due date; if you don't want to set reminders automatically, choose Tools, Options, and click the Preferences tab. Then click the Task Options button and clear the Set Reminders on Tasks with Due Dates check box.
Add details, notes, and file attachments (including document shortcuts) for the task. Click the Contacts button at the bottom of the form to link to one or more persons in your Contacts list. Click the Categories button to assign the task to categories. If you're on a corporate network with an Exchange Server, you can check the Private box to prevent anyone with shared access to your Tasks folder from seeing the details of this item.
→ Sorting your Outlook items by category is essential to managing your appointments, contacts, e-mail, and so on; see "Assigning Items to Categories".
If you plan to use the Tasks folder to track items from which you'll generate billing reports, click the Details tab. Boxes on this region of the Task form let you enter the amount of time you spend on a task, as well as Mileage details and additional notes in the Billing Information box. Click the Save and Close button to add the new item to your Tasks folder.
Tip from 
To create a billing statement with Outlook, create a custom Table view that includes the fields you want to use on your billing report. Sort or filter the list to show only the clients or companies for whom you want to generate the report. Select the rows and press Ctrl+C to copy them to the Windows Clipboard; then open a new Excel workbook and paste the copied rows into a blank worksheet range. Use formulas to translate hourly rates and mileage allowances into totals.
Items on your task list show up in red when they're overdue, and in gray, with strikethrough formatting, when you click the Mark Complete button.
If the due dates on some task items mysteriously change, see "You Want It When?" in the "Troubleshooting" section at the end of this chapter.
Entering Recurring Tasks
For tasks that repeat at regular intervals, enter the data just as you would for a one-time task, but before you save, click the Recurrence button. With one noteworthy exception, the technique for specifying how often a task recurs is essentially the same as for a recurring appointment or event. You specify whether the task repeats at daily, weekly, monthly, or annual intervals, and then enter the recurrence pattern—every other Tuesday and Thursday, the second Wednesday of each month, and so on. You can define recurring tasks that occur a set number of times—once a week for the next three weeks while a co-worker is on vacation, say—or check the End By box and enter a specific date when the task ends.
→ If you must complete the same task on a regular basis—such as a weekly sales report—use Outlook's recurring appointment feature; see "Entering a Recurring Appointment".
Unlike recurring appointments, you can define an interval for recurring tasks that are based on completing the previous instance. Let's say you want to stay in touch with a valued but hard-to-reach customer by calling roughly once a month, but you don't want to seem overly aggressive by calling too often. If you define a recurring task to call on the 5th of each month, and you don't actually connect until the 20th, you'll end up making your next call only 15 days later.
Instead, use the dialog box shown in Figure 11.14 to specify that you want to generate a new task 30 days after you complete the previous instance. Click the Regenerate New Task box, and then fill in the number of days, weeks, months, or years you want between instances. Each time you mark a task complete, Outlook creates a new Task item using the specified settings. So if you connect with your customer on the 20th, your next reminder occurs one month later, on the 20th.
Figure 11.14. Use the Regenerate New Task check box to specify that you want the due date of the next recurring task to be based on the date the previous one was completed.
Outlook adds recurring tasks to your task list one at a time. When you mark one occurrence of the task complete, the next occurrence appears in the list. If you look at your task list for the next month, you'll see only one instance of a recurring task, even if it recurs daily or weekly. When you mark each task complete, Outlook creates a new item with a new due date. If you try to delete a recurring task, you can delete just the specified instance or all recurrences.
Sorting and Filtering the Task List
Outlook's built-in views for the Tasks folder include table views—Simple List or Detailed List—that let you see all tasks regardless of due date and status. You can create custom filters and views for items in the Tasks folder as well. The following views are built-in:
Switch to the Active Tasks view to see all tasks except those where the Status is Complete or Deferred.
The Next Seven Days view shows all tasks due in the next week. It does not include overdue tasks.
Choose Overdue Tasks to see only those items for which the due date has passed. This view excludes tasks that have no due date.
Click the By Category view to see an outline style view of tasks organized according to categories you assign.
Tip from 
You can assign a single task to multiple categories; switch to By Category view, and then hold down the Ctrl key and drag to assign an item to a new category.
The Assignment and By Person Responsible views are relevant only if you assign tasks to other persons.
Choose the Completed Tasks view to see only those tasks you've marked as completed.
→ Use Outlook's Views settings to organize your Outlook data; see "Using Views to Display, Sort, and Filter Items".
If you scrupulously update the Due Date, Start Date, Status, and % Complete fields, you can use the Tasks folder to perform rudimentary project-management tasks. But when we say rudimentary, we mean it. Outlook's Task Timeline view shows start and end dates for individual tasks, but it doesn't enable you to create dependencies, balance resources, or link related projects. If you need robust project-management capabilities, look at a product such as Microsoft Project instead.