After you file

Better check to see if your return was rejected and you somehow did not notice or follow up.  If you used online TurboTax what does it say for your 2017 return--does it say "Accepted" "Rejected" "printed" or "ready to mail?"

 

And if you owed tax due for 2017 your only proof of paying would be your own bank/credit card records.

**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**