Outlook 2007 and Outlook 2010 include a much-maligned feature: the To-Do List. It seems to be a "love it or hate it" thing, with most of the people I come in contact with on the hate side. Many users ask how to remove the To-Do List and make the Task list default when they switch to the Task navigation pane. (Solution: Always use Tasks, not Outlook’s To-Do List.)
We also get a lot of questions asking how to re-order Tasks, or more accurately, why users can no longer re-order Tasks. This is usually caused by changing the view so my first suggestion is verify you are using the Simple or Detailed view then reset the view.
There are two ways to re-order tasks: change the sort order or drag the tasks up and down the list.
Drag to reorder the Tasks
To use: Select a Task and drag it to a new position. A red bar indicates the position it will be dropped in.
Not all views support dragging to reorder and when using one that supports reordering but not dragging to new groups, you can only rearrange within the group. For example, if you sort by Due date (no grouping), you can rearrange tasks with the same due date, but not drag to change the Due Date.
The tasks are reordered within their due dates:
Tip: To move a task to the bottom of the day's list, you don't have to get it exactly in the last position. When you drag it into another date range, it will snap back to the last position in it's date group.
Drag in Tasks Folders
In Tasks folders (verified in Outlook 2003 and up), you need to use a view that does not sort or group in order to re-order tasks by dragging. In the Custom view or View Settings dialog, you need both Group By and Sort set to None.
Drag to a new group
If you are using a traditional Group by View (with group headers) you can drag between groups to change the value of that field but you can't drag to change the order within a group, except when you are in the To-Do List.
Dragging between groups changes the group the Tasks belongs to. You can drag from due today to the due tomorrow group, drag to change the category, etc. Note that not all fields support dragging between groups in both the Tasks folder and To-Do List.
Published June 13 2012