Which tax year of the desktop software did you download and install?

I downloaded the one available which was 2016. When i try to do a "start new return" its will only read a 2015 file, not the 2016. Should I try to download a 2017 software and hope it will read the 2016 data? also all i'm trying to do is some hypotheticals in light of the 2017 Tax reform act.

Right I was going to mention that.  Well I did.  You do not start a new return.  You just OPEN the .tax2016 file.  Go up to File-Open

Oh yes, you might as well install the 2017 program and transfer 2016 into it.  2017 is already out so you don't need to fool around with 2016 program.  Transfer 2016 into 2017 and get started. In the Desktop program you can save your return with other names to test in.  

The new tax bill is just for 2018 and won't affect your 2017 return.  See
<a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/questions/4143905-2017-tax-reform-legislation-what-you-should-know">https://...>

190 is for missing a state program.  After you get the program installed the first thing to do before you open your tax return is to update the program and install any state programs you had. Then open your file. So you first might need to start a fake return to be able to download the state program (go to FILE - NEW TAX RETURN)

Then go to FILE -Open and find your return.

For error 190
https://ttlc.intuit.com/questions/2586090-error-190-when-opening-file-in-turbotax-desktop