I can't open prior year .tax file

[Critter]

The .tax2017 file would need the 2017 downloaded program to open it (2016 needs 2016, etc)  ... did you use the downloaded or online program for that prior year return ?  

[Anonymous]

if you used the desktop version, you need the 2017 program to open the .tax2017 tax file. 

[VolvoGirl]

If you get error 190 when trying to open the .tax2017 file you need to download the 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.