You cannot press ALT+ ~ (US keyboard) or ALT+ kanji key (JPN keyboard) to turn IME on or off in a Windows Store application in Windows 8.1.
To resolve this problem, install the most recent cumulative security update for Internet Explorer. To do this, go to Microsoft Update. Additionally, see the technical information about the most recent cumulative security update for Internet Explorer.
Note This update was first included in security update MS14-056: Cumulative security update for Internet Explorer: October 14, 2014.
This issue occurs when you move the focus out and back to a text box on a form in an application.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
See the terminology that Microsoft uses to describe software updates.