This is a problem I have seen a couple of times. It works like this: When you’re on your Windows 8 Start Screen and click or tap the Internet Explorer tile or a shortcut to a website, the desktop version of Internet Explorer launches rather than the Modern UI version.
This is simple to fix:
First, open Internet Explorer on the desktop, then select the settings cog from the top right
Then select “Internet options”:
Move to the "Programs" tab, then make sure that “Let Internet Explorer decide” is selected from the dropdown box in the “Opening Internet Explorer” section, and that the “Open Internet Explorer tiles on the desktop” checkbox is unchecked.
Press Ok. That’s it, from now on when you tap or click and Internet Explorer tile on the Start Screen it will launch the Modern UI version of Internet Explorer