First, if your taxes were never filed, then you should just use "0" for your 2016 AGI in order to file your 2017 tax return.
Next, if you need to file your 2016 return and you did start one in TurboTax - follow these instructions here
If you started a 2014, 2015, or 2016 return in TurboTax Online but couldn't file it before the shutdown, start by purchasing the TurboTax CD/Download software and installing it on your computer. Window instructions | Mac instructions
Then, follow these steps to finish your online return in the TurboTax software program:
- Download the .tax file for your prior-year return (not the PDF) and save it on your computer. We recommend saving to your desktop for ease of retrieval.
- Open your TurboTax software program, select Find a Tax File, and then browse to the tax data file you downloaded in Step 1. Select the file and click Open.
- You can now finish your return. You'll need to paper-file, as e-filing for prior years is no longer available.
Note: TurboTax software for tax year 2013 and earlier is no longer available for purchase.