You can only amend 2016 & 2017 on your computer using the 2016 & 2017 software. You must print the amended return from your computer then sign and mail the returns in separate envelopes - do not mail together of the IRS mail room will attach them together and one will probably never get processed.
Amended returns can only be mailed. It is suggested that it be mailed certified with return receipt (or other tracking service) to verify that the IRS receives it.
See this TurboTax FAQ for detailed amend instructions:
https://ttlc.intuit.com/questions/1894381-how-to-amend-change-or-correct-a-return-you-already-filed
You can check the status of the amended return here, but allow 3 weeks after mailing.
https://www.irs.gov/filing/wheres-my-amended-return
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
