Joomla 1.5.15 - Unable to Toggle Editor

I am attempting to use my toggle editor, Tinymce , in Joomla to edit my document outside of coding HTML.? However, when clicking the toggle editor, i get a blank screen. I believe that tinymce is messed up. You will be responsible for making toggle editor work.? In other words, when clicking toggle editor, you will be able to edit the code in non HTML form.