I am using LR 6 creative cloud photo subscription. I am using a MAC. I am using gmail.
I want to use "email a photo" under file menu.
I setup an email account which works with other apps on this computer.
I get the email form and when I hit send I get "failed to connect with outgoing server message".
I turned off two step verification in Google.
So are you using the built in email app in OS X, I think it is called Mail.
Then the settings you have set for the outgoing gmail outgoing server isn't correct. Could be the 2 step verification that gmail uses if you enabled that.