I created the original post and just want to reiterate what my problem is. It has nothing to do with computer memory problems, intentional or inadvertent deletion of TurboTax files, overwriting of files, etc. I have older versions of TurboTax 2017 and 2018 still on my Windows computer. After filing my 2018 return, sometime later in 2019 I was still able to open TurboTax 2018 to print out some of my 2018 forms. However, after installing TurboTax 2019 on my computer, I can no longer open my TurboTax 2018 software, either by using the desktop icon or by using the installed TurboTax 2018 files on my computer to open it. The error message I received, according to the TurboTax tech support rep, indicated a Windows problem, not a TurboTax problem. (I also cannot open the TurboTax 2017 software that is still on my computer). Working with TurboTax tech support, I even completely uninstalled my TurboTax 2018 software from my computer, and reinstalled it using the installation CD. We verified that the 2018 software did install on my computer, but I still cannot open the newly installed TurboTax 2018 software. I get the same error message, which the tech rep told me indicated a Windows problem. I have not done any further troubleshooting as I'm still head down preparing my 2019 return. I do not have any issues using the TurboTax 2019 software.
