You cannot prepare a 2017 return in Online TurboTax, which is now for 2018 only. You have to use the 2017 desktop software (CD/download.)
You can purchase 2017 desktop software as a download at this page and install it on your computer:
https://turbotax.intuit.com/personal-taxes/past-years-products/
Minimum system requirements for Windows version:
https://ttlc.intuit.com/questions/1901571-minimum-system-requirements-for-turbotax-windows-software
Minimum system requirements for Mac version:
https://ttlc.intuit.com/questions/1899173-minimum-system-requirements-for-turbotax-mac-software
Or did you already start a 2017 return online prior to the 2017 online shutdown, and want to finish that one without starting over? If so, you can download the *.tax2017 data file from your account and finish it in the desktop software. If you already paid for your product previously, TurboTax Support should furnish you the software.
The 2017 return cannot be efiled. It will need to be printed, signed, dated, and mailed. It is recommended to mail by a method that has tracking such as certified return receipt, priority mail, etc.
If you have both Federal and state returns, you need to mail each one separately to its respective tax agency.
If you are due a Federal refund, it takes about 6 weeks for the IRS to process a mailed return.
TIP: Later if you prepare a 2018 return (if not already done), it will ask for your 2017 AGI when efiling. Since you did not timely file a 2017 return, your 2017 AGI will not be in the IRS database. For that reason, when your 2018 return asks for the 2017 AGI during efiling, you would indicate your 2017 AGI is 0 (zero, single digit.)
