A few tips to always try in this case. First, try restarting your computer. Second, if you've ever plugged a game controller into your computer (such as a wheel for a racing game, a 360 controller, etc.) try plugging that in and taking it back out again, as the computer may think one is plugged in and giving input. If neither of those work, try checking input in something else, like MS Word. (If the keyboard really is doing it, you'll immediately scroll the cursor to the right if there is text in that direction) If none of those work, check your key configuration in the F1 menu to see if something else is set to the default key for right.
