Buttons of editors not showing

I've been trying for several hours to get Drupal and Wysiwig up and running.
I'm using Drupal 7.23 and installed the latest Wysiwig release (tried 7.x-2.2 and 7.x-2.x-dev).
I've installed different versions of the CKEditor and many other editors which are supported according to the installation instructions. However if I edit a content page like a book page the buttons of the editors are not loaded. I can see that something happens as there is a different frame around the Textbox depending on which editor I use, but still no buttons.
I tried to clear my browser cache and tried different browsers but no success.
Also I realized that the CKEditor I can download from the Drupal site is not supported.
The sample html pages provided with the CKEditor work perfecly on my web space.
I also tried jwysiwig, openwysiwyg, nicedit, tinymce and whizzywig without success.

Any suggestions?