By default, the tasks in a checklist are displayed in the order you created or exported them and then realigned them. To sort the tasks/remove sorting:

• Select the column headers of the default or custom columns to toggle between sorting of tasks in ascending and descending order and remove the sorting. In the following figure, tasks are sorted in descending order of their due date.
  When sorting by Status, ascending order sorting displays tasks with blank status field first followed by tasks with status in the order of their listing in the Status dialog box. For descending order sorting, tasks listed last in the Status dialog box are displayed first and tasks with a blank status field appear in the end.

  Figure: Descending order sorting by date

  

• Select the Tasks column header to restore the tasks to their default position.

You can apply sorting to only one field at a time. This feature is available only for the following fields:

• Default: Assignee, Due, and Files.

• Custom: Any Date or Drop-down type custom field.

The following right-click options that are generally available for unsorted fields are unavailable for the field to which sorting is applied:

• Hide field (generally available for all fields except Tasks) 

• Table settings

• Edit field (generally available for Status and custom fields only)

• Delete field (generally available for custom fields only)

However, the following tooltips are displayed when hovering over all column headers, irrespective of whether sorting is applied or not:  

• Click arrow icon to sort

• Drag & drop column header to reposition