The default box plots, I believe, are outlier box plots so first make sure you are not confusing the "range bars" with the box plots. The range bars can be removed under the red triangle. However, there is a way to customize the box plots. To do so: Right click>>customize>>select box plot and then there are some options for box style with additional check box options for additional features. You can also change the color of the box plots here. You do have to change each box plot individually, which is tedious if you want them all the same but useful if you want differences (such as colors).