I have a VM instance on Google Compute Engine, which is running Windows Server 2012 R2. I have my Apache web server, PHP, MySQL, FTP, and various other things running great, easily accessible from the world. I installed MDaemon Messaging Server (Alt-N's email server), which I had on my old physical box for years. I am able to use port 110 just fine, but I simply cannot get SMTP to work. Yes, I'm well aware of (Compute Engine's Blocked SMTP Ports). Knowing these blocked google ports, I would like to choose port 2525 as Mdaemon's SMTP port. I added firewall rules on the server to allow it, and I added the Compute Engine Network port exceptions as well, and of course changed the Mdaemon's server settings for 2525. I still cannot send email. Hell, I even tried port 2626 and nadda.
I understand I could sign up through google's recommended "sendgrid" that would force me to use mail.sendgrid.com, port 2525, and have a maximum of 25,000 per month limit (on free sendgrid account), but I personally think it's ridiculous needing to sign up and have limits on email when I paid $2,400 for Mdaemon email server. I should be able to use my own domain's mail.mydomain.com and authenticate through MY email server, not sendgrid's.
Is there something simple I'm missing to be able to use my own email server software on my google compute engine VM instance? Or is it just fact that this is the right I give up by choosing google's cloud server services?
