Either the first statement in the Answer above was referring to switching a 2016 desktop file to a 2016 online return, (which can't be done) or is incorrect. It IS possible for most people to normally transfer a desktop 2015 data file into a new 2016 online return. In fact, here are the directions, but I realize this won't help you at this point since you probably already know HOW to do it:
<a rel="nofollow" target="_blank" href="
https://ttlc.intuit.com/questions/1900883-transfer-last-year-s-return-into-turbotax-online">https://...>
If your 2015 file was password-protected, that's why you cannot transfer it into a 2016 online return. And if Windows XP, the password cannot be removed without a Windows 7 or higher computer.
EDITED: See next comment below. A user reports a Mac computer with OS X 10.9 or higher can remove it as well.
