CKEditor doesn't appear when editing a node

Check the following instruction: http://drupal.ckeditor.com/troubleshooting#4
First of all make sure whether CKEditor actually is enabled there (on that page/field) or whether the problem is in some javascript error.

I had this problem and discovered that it happens when I have another tab with yahoo mail open in firefox. It seems that ckeditor is trying to get some properties from another tab and causing a javascript error. Closing other tabs makes ckeditor work again so I assume the problem is not in the drupal module.

@bongo_john_uk - sounds really strange. CKEditor does not look into other tabs... that could be also a problem with some FF extension.
Closing issue as the original reporter did not reply.

I'm also experiencing the same problem. Its happening in firefox 3.0.11, but it works fine in the latest version of Firefox on another computer. I think I just need to upgrade my browser.

I seem to have this problem, where content type name consists of more than one word...

For example, when defining fields to INCLUDE, I had to write two rows for such fields/content types:

video-item@*.edit-body
video_item@*.edit-body

If I just write video-item@*.edit-body, CKEditor shows on the node/add form but not when editing. Writing video_item@*.edit-body seems to do it for the node/%/edit form.

Okay, so I had this issue as well. Here was my cause for those of you who did the same thing I did. I moved the print of my template $scripts to the foot of my templates to assist with page loading and remove css image loading race conditions. This is fine and dandy, except when modules insert js via drupal_add_js() targeted at "footer". It appears that the script is then dropped at the bottom of the node body. My scripts are below that, so I was getting a javascript error because "drupal" was not defined. When I poked around I found this line:

drupal_add_js($module_drupal_path .'/includes/ckeditor.utils.js', 'theme', variable_get('preprocess_js', FALSE) ? 'header' : 'footer');

The important part is: variable_get('preprocess_js', FALSE) ? 'header' : 'footer' this logic puts the code at the bottom of the node if the js is not optimized (compressed)(set on the performance page) or in the header when the code is optimized. Why the location would change based on the length of variable names and the amount of whitespace in the javascript is beyond me, but replacing the logic with "header" worked fine for me (since my header js was re-located to the bottom of the HTML body). This is not the ideal solution, but it works in our production environment either way, so when it breaks again it will only be in dev and staging, but I would suggest looking into why the code has to move based on it's size in order to work.

#6 had the solution for me, you have to have a dash AND an underscore.
I never, EVER would have thought to do that. You saved me. Thank you.