The TurboTax online editions are only for tax year 2017. Remove any tax data that is not for tax year 2017 which was previously entered.
To complete tax returns for prior years using TurboTax you would need to purchase and install on your personal computer one of the desktop editions for each tax year required (2014 thru 2016) from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/
Prior year tax returns can only be printed and mailed, they cannot be e-filed.
When mailing multiple tax years use separate envelopes for each year.
