My bet is, the reason you couldn't claim the student on your tax return in previous years, is because you didn't read the screen (as most do not) and therefore incorrectly indicated the student did not live with you for "the entire year". It's a common mistake that can be avoided by reading the information presented on that screen. The small print really does matter, big time.
IN the desktop version of TurboTax, the small print I'm referring to is on the screen "Tell us a bit more about [name]". It's the screen in the dependents section under the personal info tab where you select the number of months the dependent lived with you. That small print reads, "If your child was away at college, count the number of months away as having lived with you".
If you need to, you can amend your tax returns back to and including 2014 and get any additional refund you may be due, "PROVIDED" your dependent did not take any of the education tax credits or take the self-exemption on their tax return (if they filed one). Don't bother amending the 2013 return for additional refund. The 3-year grace period for that is past, and if you would be due a refund, you will not get it anyway.
