The switch emulator files have a problem running in IE 11.  (This problem does not occur in the actual product, just on the emulator pages hosted on cisco.com.) 

The recommended solutions are to use either IE 10,  Chrome, FireFox, or download the emulator files and host the emulators locally.

To download the emulators to your local device, scroll down the Cisco Small Business Online Emulator page to find the “Hosting Switch Emulators Locally” section.”