The TurboTax software is available for the current tax filing year (which is 2016 as of this post) and three years back. TurboTax does not support their software more than 3 years back. For a prior year return, you can not use the online version of TurboTax. The only version is only for the currently active tax year.
You will need to purchase the TurboTax software for each individual tax year you need to complete. After you purchase it via CD at your local retailer, or as a downloadable installation file from TurboTax, you will need to physically install the program on your computer. (I doulbt you will find TurboTax for past year's in your local store.)
Once installed, click the TurboTax icon on your desktop to start the program and just follow the prompts. You can purchase the prior year programs at https://turbotax.intuit.com/personal-taxes/past-years-products/ ***MAKE SURE*** you are under the correct tab for the tax year to be purchased. You have to purchase the program for each individual tax year you need. You should start with the oldest tax return first, and work your way forward.
Note also that you can not e-file a prior year tax return either. The IRS says so. You have to print it, sign it and mail it to the IRS. You should mail each tax return in a physically separate envelope. When you select the "Print and File" option it will also print mailing instructions. The address you mail to **MAY NOT BE THE SAME** for each tax year either. So watch that.
If you need help in the process of preparing these tax returns, you can always post your question or query in this forum. However, make sure you clearly identify what tax year you need help with, as tax laws change year to year and you don't want to be given 2016 information for a 2013 tax return.
