@ggrustin
Depends on whether you you used the "Desktop" or "Online" software for the downloads.
1) if you download the PDF files from your "online" account (Only if you prepared your taxes "Online")...then those should be able to be opened on any computer. But if you did use the "Online" software to prepare those years, then the PDF files are still in whatever account you used...and you can download them again to any new computer you have. (If you are on a windows computer...do not use the Edge browser to download, use either IE11 or Chrome)
2) If the downloads were ".tax2105, .tax2016, and .tax2017" data files...whether from Online software, or form Desktop software on another computer, then you have to copy those files from the USB to the hard disk on a full Windows or MAC computer....then install the 2015, 2016, and 2017 desktop software on that computer, install any sate(s) used in those datafiles. Only then you can i open those datafiles in each year's software, and then create new PDF files.. But you have to install the desktop software on your own computer for each year involved.
3) If you cannot find your 2017 AGI by one means or another, then you may have to switch to file-by-mail, then print out and mail in your Federal and State tax returns to each appropriate agency. When file-by-mail is done....then YOU have to print and mail them in. Use a tracking method at the Post Office counter...and make sure you sign.date each, and attach the appropriate copy of any W-2 forms you have, along with copies of any other tax forms that show federal or state withholding.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
