Sorry they only sell and support the last 3 years. So even if you can find 2015 to install you won't be able to update it or download any state programs. You have to find a local accountant or tax place.
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
Don’t forget your state. And you will have to print and mail your returns. So be sure to attach copies of your W2s and any 1099s that have withholding on them. You have to mail federal and state in separate envelopes because they go to different places. Get a tracking number from the post office when you mail them for proof of filing.
