In Firfox only (don`t have this problem in any other apps), when I try to type certain characters, alternate characters appear e.g. `É` instead of `?` or `/` instead of `#`.

Question

This problem seemed to fix itself for a period of time but now it`s returned. It`s quite frustrating because to type some of the characters that I need, I have to use the Windows character map or go to other apps, type the character that I need, copy it, return to Firefox and paste.

Answer 1

See:
* http://windows.microsoft.com/en-US/windows-vista/The-Language-bar-overview - The Language bar (overview)
It is possible that you are switching the keyboard layout by accident.
* Make sure that you have the Language bar visible on the Windows Taskbar.
* You can do that via the right-click context menu of the Taskbar: Toolbars > Language Bar.
* Check the keyboard language (keyboard layout) setting for the application that has focus via the icon on the Language bar.
* You need to do that while Firefox has focus because Windows remembers the keyboard layout setting per application.
* The default keys to rotate the layout is a combination (Ctrl+Shift or Alt+Shift) that can easily be used in Firefox to activate a menu item.
* To avoid an unintentional switch assign a specific key sequence (Alt/Ctrl+Shift+number) to select keyboard layouts and remove the key combination to rotate layouts (Alt+Shift or Ctr+Shift)
* Vista: Control Panel > Regional and Language Options > Keyboards and Languages > Change keyboards > Advanced key settings > Change key sequence