Diagnose site display error in Windows 8 compatibility view

I built a site for a client in June 2013. Everything displays in Chrome, Opera, Firefox and Safari.
My client is using a PC, loaded with Windows 8 and IE10. He says the site doesn't seem to completely load, it has that broken icon in the address bar and also it keeps loading (little wheel keeps turning).
The site is http://getonyourbike.com.au/