Troubleshooting user count when using SMTP Proxy server



There are two methods to fix the higher user count issue:

  • Option 1 - Configure your actual email server (not Xeams) to reject invalid email addresses. Every SMTP server has a different way of rejecting invalid users. Click the appropriate link below corresponding to your server.

    Using Proxy Server with Exchange 2013/2016

    Microsoft changed how invalid emails are rejected in Exchange 2013/2016, which broke the ability of Xeams Proxy Server to detect an invalid user. Therefore, option 1 is not available when using MS Exchange 2013/2016. You can either use option 2 described below or use the regular SMTP server for inbound email, which supports DRV. Refer to this article for details.


  • Option 2 - Use Active Directory to reject invalid users. The following configuration must be set in order for this to work: Enable and configure integration with Active Directory and select reject invalid users (See image below):



    Next, check the Use Active Directory option under Smtp Proxy Configuration (See image below):