#displays instead of £ in word. Why?

[JC Silver]

I used to be able to type the £ sign when I pressed "shift"+3. Now I keep
getting the #. What have I pressed to get this? My regional language is set
to English UK

 

[grammatim]

You seem to have switched to a US keyboard. _Maybe_ this is toggled by
Alt+Shift; if that doesn't work, go to Start > Control Panel >
Regional and Language Options > Languages > Details and under English,
Remove all the keyboards you don't expect ever to use (such as US and
Dvorak). (Don't worry, you can get them back if you ever need them.)