After you file

Online is only good for the current year 2017 so you have to buy the Desktop CD/Download program here https://turbotax.intuit.com/personal-taxes/past-years-products/     

Or you can get the blank forms from the IRS and do them by hand.  Either way you will have to print and mail prior year returns.  And send each year in a separate envelope so the IRS doesn't miss any.

2016
Here are some blank forms & instructions for 2016
1040 https://www.irs.gov/pub/irs-prior/f1040--2016.pdf     
Instructions https://www.irs.gov/pub/irs-prior/i1040gi--2016.pdf

1040A https://www.irs.gov/pub/irs-prior/f1040a--2016.pdf    
Instructions https://www.irs.gov/pub/irs-prior/i1040a--2016.pdf

1040EZ https://www.irs.gov/pub/irs-prior/f1040ez--2016.pdf    
Instructions https://www.irs.gov/pub/irs-prior/i1040ez--2016.pdf

2016 Tax Tables https://www.irs.gov/pub/irs-prior/i1040tt--2016.pdf
Publication 17 Tax Guide for 2016 https://www.irs.gov/pub/irs-prior/p17--2016.pdf




2015
Here are some blank forms & instructions for 2015
1040 https://www.irs.gov/pub/irs-prior/f1040--2015.pdf     
Instructions https://www.irs.gov/pub/irs-prior/i1040gi--2015.pdf

1040A https://www.irs.gov/pub/irs-prior/f1040a--2015.pdf    
Instructions https://www.irs.gov/pub/irs-prior/i1040a--2015.pdf

1040EZ https://www.irs.gov/pub/irs-prior/f1040ez--2015.pdf    
Instructions https://www.irs.gov/pub/irs-prior/i1040ez--2015.pdf

2015 Tax Tables https://www.irs.gov/pub/irs-prior/i1040tt--2015.pdf
Publication 17 Tax Guide for 2015 https://www.irs.gov/pub/irs-prior/p17--2015.pdf