The Home of Spock/McCoy Fiction
Well, this is a little embarassing given the number of times I typed the word incompatible when discussing Internet Explorer. If you wish use the tinyMCE Editor in the newer Internet Explorer, simply click on Compatibility View icon in the address bar (it looks like a torn piece of paper) to the left of the Refresh and Stop icons. It should turn a darker shade when the feature has ben turned on. Depending on how you have your browsing history maintenance set up, you may only need to do this once.
My apologies, I rarely use Internet Explorer and had completely forgotten the feature existed.