[kwlug-disc] Postfix/GApps Mail going to spam

[Charles M]

Evening all. I've been reworking my web site, setting up a new
installation on my VPS. I've got my site set up but mail sent from the
site is being caught in SPAM.

I've signed up for the $50/year Google Business Apps/mail and set up
myname at mydomain.com. Also set up the Google MX records on my VPS. I
installed Postfix but I think I must have made a mistake somewhere
since mail is getting caught in spam.

Could it be that I'm not pointing to the Let's Encrypt certificate or
that the Let's Encrypt certificate points to www.mydomain.com and not
just mydomain.com or is it something else in the /etc/postfix/main.cf
that could be causing the issue?

Or will it simply do this because I'm using Google Apps rather than
setting up a full mail host on the VPS?

Cheers and thanks!

Charles