Greetings, I will certainly hope someone will be able to provide some enlightenment to my problem. Currently, I have 2 joomla sites, layout and menus are a replicate of the other.
I noticed that on both Joomla, I will occasionally encounter "Unable to send mail" after a form submission.
Is this the fault of my server, or the fault of Joomla's PHP Mailer ? I will certainly love to approach my hosting company for a solution but I do not want to place a false accusation on them.
By default, Joomla will use PHP's mail() function, although you can set it to use other methods (sendmail, SMTP) in the Global Configuration on the Server tab.
The best way to test this would be to set up a small PHP script that sends a message through mail(). Next time you see the message, try running the small script and see if that one fails as well.
I personally preffer using an SMTP server for mailing purpose. I guess your hosting company has provided something like smtp.yourdomain.com
You may use it.
Else, you can use the gmail server smtp.gmail.com
It wont disappoint you for sure.