I have big elaborate on SMTP configuration in DNN. I am using ver 7.2.0.
I have noticed that since some time every site has its own SMTP configuration section. I have noticed some issues about it.
1. I assume that if I configure SMTP on site level it won't propagate elsewhere. But it does!!! If I configure SMTP on site level it is being copied to portal level SMTP configuration. So if I have more than one site, and I configure each of them with unique SMTP conf, always the last one wins...... and is being used to send e-mail.
2. Even if SMTP propagates to portal level from site level configuration - which is totally wrong - it will send e-mails using the SMTP account from configuration section (site level which is expected). But it doesn't!!! As a from e-mail it uses super user - or administrator - e-mail in "From" field. It is a surprise!!!
Please take into consideration the above conclusions.