Only the 2015 tax data file can be transferred to the 2016 return when you start a New Tax Return for 2016. Does the tax data file have a file extension of .tax2015?
Do you have the 2015 tax file on your computer? It ends in .tax2015. You need that to transfer into 2016. First thing you do is start a new return and it should find all your 2015 files and ask if you want to transfer them.
Here's how for Mac:
<a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/questions/1901265-transfer-last-year-s-return-into-turbotax-for-mac">https://ttlc.intuit.com/questions/1901265-transfer-last-year-s-return-into-turbotax-for-mac</a>
This is what I tried to do, but the 2016 TurboTax would not open the .tax2015 file because it was displayed as a grayed out option.