Can I still e-file a 2016, 2015, or earlier tax return?
If you’re looking to access a previous return that you already filed (and not file a return for a previous year) follow these instructions.
It's too late to e-file a 2016, 2015 or earlier tax return if you're filing a personal (1040) return, which has an e-filing window from January to mid-October after the tax year ends.
For example, the 2016 tax year ended on December 31, 2016, so that means personal returns were "e-fileable" in TurboTax from January through mid-October of 2017.
2016 corporate (1120) and partnership (1065) returns are the only prior tax year/entities that can still be e-filed.