Do you have the file ending in .tax2020? Why do you need to open it? If you only need to start 2021 you just transfer the .tax2020 file. You don't need to open the file in the 2020 program.
Oh and don't try to open it from the flash drive. First copy or move it to the computer hard drive.
To open 2020.......
After you get the program reinstalled 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.
