What computer operating system are you using? Did you inadvertently choose a different keyboard language for the operating system?
I'm using Windows 7 Home Premium, and no, I haven't changed my keyboard language (English (Canada) -US).
Did you check your keyboard layout? Similar problem I know, speciallly on Windows, where the keyoard layout was not of the region, language or type as it was installed. E.g. here in Germany we have QWERTZ (called after the keys in the first letter line), but on Windows it changes to easy to a different installed layout like QWERTY (of various languages).
The "-key in US-QWERTY is in other key layouts:
- Canadian french CSA È
- German (Germany & Austria): Ä
- Spanish Spain: :
- Spanish ISO: ¨
The ?-key in US-QWERTY is in other key layouts:
- Canadian french CSA É
- German (Germany & Austria): _
- Spanish Spain: Ç
- Spanish ISO: _
I strongly recommend to deactivate keyboard layouts on Windows computers without any hardware available of that layout. Anything else you can't use anyway and causes troubles by accidently changing the layout into a not existing input variation. E.g. I have often people working on a Windows Notebook with only German keyboard, so it makes no sense to have a different layout available. If you get a different keyboard (like Russian or Helenistic Language) you can add it in System Settings again as available.