Using the virtual keyboard, I cannot insert the (at) symbol or the (pound) symbol.
I'm using a Portuguese (Portugal) QWERTY keyboard. Neither of these keys work on the physical keyboard, either.
I tried some other keyboard configurations with other languages, and @ and £ work in certain configurations, including the touch keyboard. It doesn't work on the Portuguese one, but if I switch to English it works.
EDIT: Is works when inserting password on the login page of Windows.
EDIT2: And because we are dealing with Windows, for no reason it started working again... Well.