Christy, I found a temporary fix:
- open wp-admin/admin-header.php with a text editor
- add the following somewhere inside the
<head> tag:
<script type='text/javascript' src='<?php bloginfo('url'); ?>/wp-includes/js/tinymce/plugins/wordpress/editor_plugin.js'></script>
This is a total hack, I am sure this is not the proper place to add javascript includes. wp-includes/script-loader.php appears to be the proper script to add this. I am hesitant to edit this file for several reasons. First, I have only been using wordpress for a week so I am not familiar with how it works under the hood. script-loader.php looks to be a critical file used throughout WordPress so I didn't want to break other things to fix this problem. Finally, I don't know what caused this to break. The editor worked this morning. I made several hours of changes to wordpress today before realizing that it was broken. I suspect a plugin may have caused this problem but who knows...
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In case it is of use to someone, this is what I did to troubleshoot the problem (wordpress 2.3.2) :
When trying to edit any post (new or old), the Code tab did not work. When it was clicked, I noticed two javascript errors (using firebug). As mentioned in previous posts, the error is: switchEditors is not defined onclick(click clientX=0, clientY=0)
I searched for the text switchEditors in every file included in WordPress 2.3.2. It only refers to a javascript function in wp-includes/js/tinymce/plugins/wordpress/editor_plugin.js
Viewing source for wp-admin/post.php reveals that the file: editor_plugin.js is not included in the <head> of the document. As a quick and dirty fix, I edited the header file for the posting pages: wp-admin/admin-header.php
Hope this helps.