You cannot use the current online software to prepare a 2016 return. Online preparation and e-filing for 2016 is permanently closed. You have to download 2016 software and then print, sign and mail your return. If you already paid for your TurboTax software, you can contact customer support to push a download of the software to you.
https://ttlc.intuit.com/questions/1899646-what-if-i-missed-the-october-16-filing-deadline
To finish a prior year return started in TT online:
https://ttlc.intuit.com/questions/2559403-how-do-i-finish-a-prior-year-return-that-i-started-in-turb
Remember to prepare your state return as well—if you live in a state that has a state income tax.
When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s. Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS received the return.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
