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I had an installation of Umbraco that didn't show all of the icons in the editor. Every node clicked only showed save, publish, undo, and the style dropdown. Here is what I did to make them appear: (18.104.22.168 and IE 6). Go to Tools > Internet Options and set the temporary internet browsing history to "Automatic" and bump the space up to at least 50mb. That fixed our issue, and the icons appeared.