You have to see a tax professional for this. TurboTax only supports their software for the current tax year and 3 years back. You flat out can NOT use TurboTax to fix the 2011, 2012 and 2013 returns, and you *have* to amend 2011 first. So you need to see a tax professional in your local jurisdiction who is licensed, certified and qualified to deal with this.
For amended returns more than three years back, if the amendment will result in you getting a refund, you will not get it. The 3-year grace period is past. But you may need to file it anyway, so that carryovers of your basis will be correct. This is why you *must* seek the services of a tax professional on this.
