Sorry, TurboTax no longer supports those years. You might be able to purchase those years from Amazon. Or, search the internet. Just be aware, if you purchase those TurboTax years, you may not be able to get the updates for the 2015 year. You should be able to manually update 2016.
To manually update your prior-year TurboTax for Windows software, follow the same instructions as above, except substitute the tax year you need for Step 2:
2015 and earlier updates are not available, as these past-year versions are no longer supported.
Sorry, TurboTax no longer supports those years. You might be able to purchase those years from Amazon. Or, search the internet. Just be aware, if you purchase those TurboTax years, you may not be able to get the updates for the 2015 year. You should be able to manually update 2016.
To manually update your prior-year TurboTax for Windows software, follow the same instructions as above, except substitute the tax year you need for Step 2:
2015 and earlier updates are not available, as these past-year versions are no longer supported.
Here's a link for the manual update for 2015 for Windows. BUT - This is only for federal. I don't think there is any way to get the state software or state updates for 2015.
2015 manual update (R42 - 116 MB)
You might already know this but in case you are not aware, you are too late to receive an income tax refund for 2015 or 2016, even if the Form 1040's show a refund. Those refunds have been forfeited. But if you owe tax due, you are subject to late filing penalties and interest, which will not be calculated by TurboTax. Those amounts will be calculated by the IRS, and they will bill you at a later time after they receive the returns and your payments for the tax due as shown on the tax forms.