To access your current or prior year online tax returns sign onto the TurboTax website with the userID you used to create the account - https://myturbotax.intuit.com/
Scroll down to the bottom of the screen and on the section Your tax returns & documents click on Show. Click on the Yearand Click on View adjusted gross income (AGI)
You can also get free transcripts of your federal return from the IRS - http://www.irs.gov/Individuals/Get-Transcript
See this TurboTax support FAQ for the AGI - https://ttlc.intuit.com/questions/1900840-how-do-i-find-last-year-s-agi
If your tax return continues to be rejected by the IRS even with the correct 2016 AGI being entered then you will have to print and mail the tax return. See this TurboTax support FAQ for printing a tax return for mailing when using the online editions - https://ttlc.intuit.com/questions/1944348-how-do-i-print-and-mail-my-return-in-turbotax-online
