I can't get my php to send email from my forum due to my server setup so I'll be needing to send email via gmail instead. Unfortunately, I can't get it working either until I digged into this:
Gmail now is working for my forum.
Next, should we fix this in ElkArte?
Interesting! Does gmail have volume limitations that you're aware?
They have limits and you can refer them here:
https://support.google.com/a/answer/166852?hl=en
https://support.google.com/a/answer/2956491#sendinglimitsforrelay
I think using gmail in our case is subject to the first one because I think relay is somewhat different (I may be wrong about this :D).
http://stackoverflow.com/questions/5294478/significance-of-localhost-in-helo-localhost
https://groups.google.com/forum/#!topic/golang-nuts/Pt_H9d3QVXg
What port are you using?
Try 587.
Tested and that port 587 is definitely not working with default 107 Mail.subs.php or after the suggested fix. Only port 467 is currently working with the suggested fix.