For a long time I have been using Right Alt+U as a shortcut for starting an application in my OS. It's the one where you type the name of an app in the Start menu, open Properties and under Keyboard shortcut you bind a key to it (e.g. http://imgsrv.worldstart.com/shutdown_keyboard_shortcut_2.jpg).
But recently it stopped working for no apparent reason (I haven't changed anything). Today I found out that when I press Right Alt+U in any text editor/field it produces a euro sign: €. I don't know if it also did that before when my shortcut worked (i.e. launched my app).
My question is: how do I make my keyboard shortcut work again (i.e. start an app)?