We use a hosting company for our website but we have our mail servers hosted by our isp with our website domain; @sample.net.
On the website we have a contact form which emails email@example.com after the user submits it.
Using the default setting:
SMTP localhost sendmail_path /usr/sbin/sendmail -t -i
And custom settings:
I was able to successfully send the mail to external domains other than @sample.com. After looking into this I believe it is because the SMTP is localhost and not properly pointed at our ISP mail servers.
What value would I put in the SMTP if I have an external company hosting the site with our mail servers being hosted by our ISP?