I don't know if you are using a MAC or PC. If you are using the Windows version, launch your desktop TurboTax program that you installed from the CD. If there is no rectangular shortcut icon showing at the main screen, then click on the FILE menu in the upper left corner of the TurboTax GUI. In the dropdown menu choose "Open Tax Return", and an explorer directory will pop up. Does it show your *.tax2018 data file?
If you are using Windows, the default location is the Documents folder, but you could have saved it anywhere.
If you are using the desktop version, then all *.tax2018 data files are saved on your system. Search your entire computer system for any file ending in the *.tax2018 file extension.
