Have you ever suddenly had odd characters appearing when you type, or perhaps not odd but not what you expected? This is quite common with Dell PC’s in Canada that by default have additional language options enabled, but I am sure it happens in other parts of the world as well and with other PC models. You may see for example an ” É ” when you type a ” ? ”
Windows has a “switch” to enable/disable the alternate language keyboard. The Windows 7 default is to hold the left alt key and press the corresponding shift key at the same time. If you prefer, you can change the characters used to control the “switch” or disable it all together under Control Panel | Region and Language | Keyboards and Languages | Change Keyboards | Advanced Key settings | highlight “Between input languages” and click Change Key Sequence. There are other shortcuts in the same location you may wish to edit while there.
Updated Feb 5/2012:
It seems some Dell computers, even though under Region and Language keyboard settings as noted above are set to use the left alt+shift key as the combination to switch between keyboard language styles, they actually use the left ctrl+shift keys.
Also, you may have decided to permanently change the language and keyboard settings under: Control Panel | Region and Language | Keyboards and Languages | Change Keyboards | General. If so, note that it will only affect the logged on user, it does not affect the actual initial computer logon. To do so you must also go to Region and Language | Administrative | Copy settings | and check the box “Welcome Screen and system accounts”. Checking the other option, the “New user accounts” box, will apply the same edited Region and Language settings to any new user accounts you create, but if there are other existing user accounts to which you want to apply the changes, you will have to do so manually one by one.