If you want strict chronological order, without threading: View|Sort by|Unthreaded View|Sort by|Date View|Sort by|Ascending The last one might need to be "Descending" - I can never work out what these two words actually mean in this context. You can also do all this by clicking icons but that's harder to describe. Click on the "date" button at the top of the date column to sort by date. Click again to reverse sorting order. At the left hand side (usually at the left but it's movable) there will be a button that selects and deselects threading. On mine it's a speech bubble, but the icon depends on the theme in use. Clicking this will toggle between threaded and unthreaded.