I should be able to use my own domain's and authenticate through MY email server, not sendgrid's. I understand I could sign up through google's recommended 'sendgrid' that would force me to use, 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. A sample VB project called MDUserEdit is included in the DocsAPISample COMMDUserEdit directory off of the root MDaemon directory. 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. OVERVIEW - The MDUserCOM is a set of COM objects that provide interfaces which simply wraps MDaemons MDUSER.DLL API for ease of use with Visual Basic. Knowing these blocked google ports, I would like to choose port 2525 as Mdaemon's SMTP port. Yes, I'm well aware of ( Compute Engine's Blocked SMTP Ports). I am able to use port 110 just fine, but I simply cannot get SMTP to work. I installed MDaemon Messaging Server (Alt-N's email server), which I had on my old physical box for years. I have my Apache web server, PHP, MySQL, FTP, and various other things running great, easily accessible from the world. It blocks virtually all known dangers and prevents infestation by newly released threats by combining multiple powerful. I have a VM instance on Google Compute Engine, which is running Windows Server 2012 R2. MDaemon AntiVirus provides the next generation of antivirus and spam protection for the MDaemon Email Server by halting viruses on all inbound and outbound email at the server before its passed on to the client, providing a shield to stop security trouble before it starts.

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