IE9 seems to be ignoring the style sheets from RadStyleSheet for a custom skin if it is not running in compatibility mode. I have a custom skin from the Visual Style Builder that I made into an assembly and added as a DLL to my website. I tested it on a sample page and this is the error that IE gives me:
SEC7113: CSS was ignored due to mime type mismatch
I'd prefer to keep away from compatibility mode. Thanks for the help.