How do I eliminate the horizontal scroll bar at the bottom of my email message box?

When I'm typing an email message why do I have to contend with an active horizontal scroll bar which I must move, left and right, to review what I'm writing? I have a friend who uses Yahoo email and he does not have a moving scroll bar.|||Usually the reason for the scroll bar is because the viewable screen window is too narrow to view the entire area. So you will need to adjust either your screen resolution or the size of your viewable area. Do you keep your favorites column on the left? If so try making it narrower.