This week we stumbled across an IE-browser issue whereby the solution was simple, but to get to the solution took us a lot of time.
Hopefully this post will save someone to go through the same path to find the solution :-).
We had a set of users (authors) working on IE8 and CQ5.5, whenever they clicked to see a dialog (page properties etc) the following error came up.
After trying a lot of things we got help from our support department and they were able to find the cause for this.
It was the setting “Enable native XMLHTTP support” it was disabled in our case and it should be enabled.
After enabling this setting the author interface was working again correctly.