Intermittent email send message failed

Had a good scan of the whole forum and didn't see anything like this .... So hope for some help:
- I have intermittent "email send message failed", some times working, some times not ...
- I use a dedicated gmail address for sending the emails, I tested that address and it works
==> any way I could debug why some times the email would fail to send ? any experience you would have ?
Thank you and much appreciated

Hello,

I actually responded to this post a few minutes ago and shamelessly whined about the fickle email capabilities of Indigo AND/OR the big name email servers not playing together well. Then I decided to dig into the matter again, finding this post I have not come across before:

viewtopic.php?f=104&t=12990&p=167555&hilit=email+re+send+failed#p167555

The solution is a little odd and I really didn't expect it to work, but sure enough, it did! I now have the use of email again after three years of lost capability and my Event Log cluttered with "email send authentication failed". Maybe this is the solution to your intermittent problem as well. Good luck!