Thanks @VolvoGirl
Specifically I guess that means that when you click the button to submit your returns by e-file you have to be signed into your TurboTax account.
Regarding the PIN.
I just took a look at the filing process by running through the filing screens on TurboTax and I see that on the page to electronically sign, it gives you a PIN # (there is already a number in the "PIN" field).
I just can't remember what the significance of that is. What do you need that PIN number for?
