Explorer Browser not supported

this plugin works perfectly in chrome and mozilla but not work in explorer …i have used this plugin shortcode in welcome popup plugin page..to get full screen on page in which required but its not working in explorer ..pop up window comes perfectly. but after that nothing happen u can check
this url usmle.org.in/gimslecture/?page_id=2195 on chrome mozilla and explorer.

http://wordpress.org/plugins/native-fullscreen/