Didn't you already post this same question earlier? I provided a possible answer there. I'll repost here:
You may have more than one keyboard language installed, if you do a certain key combination it can activate it, try this:
Click
start, type
keyboard language in the search box, click
change keyboards or other input devices, select the
keyboards and languages tab, click
change keyboards button, check to see if there are any keyboard languages installed other than English, if so delete them.
