TurboTax for 2018 is no longer available or supported. If you want to file for 2018 even though you will not get the refund, you will have to look for other tax software that is still available for 2018. You could download the blank forms and instructions from the IRS web site and fill them out by hand, but I don't recommend that. Unless you are experienced at preparing tax returns on paper, it's too likely that you will make mistakes.
