Go to this website to purchase a download of the 2016 desktop editions - https://turbotax.intuit.com/personal-taxes/past-years-products/
A 2016 tax return can only be printed and mailed, it cannot be e-filed.
Also note - TurboTax for 2016 does not support Windows XP.
See this TurboTax support FAQ for the Windows system minimum requirements - <a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/questions/1901571-minimum-system-requirements-for-turbotax-windows-software">https://ttlc.intuit.com/questions/1901571-minimum-system-requirements-for-turbotax-windows-software</a>
If you started online last year here's How to finish a prior year online return <a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/questions/2559403-how-do-i-finish-a-prior-year-return-that-i-started-in-turbotax-online">https://ttlc.intuit.com/questions/2559403-how-do-i-finish-a-prior-year-return-that-i-started-in-turbotax-online</a>
To do 2016 for free. Here are some blank forms & instructions for 2016
1040 <a rel="nofollow" target="_blank" href="https://www.irs.gov/pub/irs-prior/f1040--2016.pdf">https://www.irs.gov/pub/irs-prior/f1040--2016.pdf</a>
Instructions <a rel="nofollow" target="_blank" href="https://www.irs.gov/pub/irs-prior/i1040gi--2016.pdf">https://www.irs.gov/pub/irs-prior/i1040gi--2016.pdf</a>
1040A <a rel="nofollow" target="_blank" href="https://www.irs.gov/pub/irs-prior/f1040a--2016.pdf">https://www.irs.gov/pub/irs-prior/f1040a--2016.pdf</a>
Instructions <a rel="nofollow" target="_blank" href="https://www.irs.gov/pub/irs-prior/i1040a--2016.pdf">https://www.irs.gov/pub/irs-prior/i1040a--2016.pdf</a>
1040EZ <a rel="nofollow" target="_blank" href="https://www.irs.gov/pub/irs-prior/f1040ez--2016.pdf">https://www.irs.gov/pub/irs-prior/f1040ez--2016.pdf</a>
Instructions <a rel="nofollow" target="_blank" href="https://www.irs.gov/pub/irs-prior/i1040ez--2016.pdf">https://www.irs.gov/pub/irs-prior/i1040ez--2016.pdf</a>
2016 Tax Tables <a rel="nofollow" target="_blank" href="https://www.irs.gov/pub/irs-prior/i1040tt--2016.pdf">https://www.irs.gov/pub/irs-prior/i1040tt--2016.pdf</a>
Publication 17 Tax Guide for 2016 <a rel="nofollow" target="_blank" href="https://www.irs.gov/pub/irs-prior/p17--2016.pdf">https://www.irs.gov/pub/irs-prior/p17--2016.pdf</a>