Is there any workaround for not being able to loading a .tax2015 in TurboTax 2015? I have a saved .tax2015 document on my computer and have not been able to reopen it.

To open a 2015 tax file you must have the 2015 downloaded program installed on your computer then update it and install any state programs needed.  Where are you having trouble with this process ?  Do you have a MAC or Windows OS ? 

I have the 2015 downloaded program installed and updated. I'm running on macOS Mojave 10.14.6 and have already done the Terminal command FixTY14AndTY15. The issue is that I will do my taxes, save, can see the file saved in my Documents, but when I reopen TurboTax, it's all gray! So I have to start over.