See the following TurboTax support FAQ on accessing a copy of a 2015 or earlier return completed using the online editions -https://ttlc.intuit.com/questions/1900748-how-do-i-get-a-copy-of-a-return-i-filed-in-turbotax-online
Once the PDF has been downloaded to your computer, you can view or print the return with any PDF compatible viewer, such as Adobe Reader.
You have to sign onto your TurboTax online account with the exact same userid and password you used to create the account.
If you may have forgotten some of your login information, see the following TurboTax support FAQ -https://ttlc.intuit.com/questions/1901535-forgot-your-turbotax-user-id-or-password
Or you may have multiple accounts, see this - https://ttlc.intuit.com/questions/1901486-problems-associated-with-multiple-turbotax-accounts
If you receive a message that your tax return is Locked or that you need to pay for the account, see this TurboTax support FAQ - https://ttlc.intuit.com/questions/2926523
If you still cannot access your account, you can contact TurboTax customer service/support through their contact website during business hours.
See this TurboTax support FAQ for a contact link and hours of operation - https://ttlc.intuit.com/questions/3401489
Submit your question/problem during business hours and then use the option for Call (a phone number will be provided for Call) to speak directly with a TurboTax agent -
Note: The Call option will not be available when TurboTax Support is closed.
If you used the desktop CD/Download editions installed on your computer, the only copy of your tax data file and any PDF's will be on the computer where the return was created. TurboTax does not store online any returns completed using the desktop editions.
You can also get free transcripts of your federal return from the IRS - http://www.irs.gov/Individuals/Get-Transcript