You have to download the data file ending in .tax2016 and install the Desktop program to open it. How to finish a prior year online return https://ttlc.intuit.com/questions/2559403-how-do-i-finish-a-prior-year-return-that-i-started-in-turb...
If you paid for 2016 call in and ask for the program download. Contact Customer Service during office hours M-F 5am-5pm Pacific (8-8 Eastern) https://support.turbotax.intuit.com/contact/