Troubleshooting user count when using regular SMTP server

There are a couple of methods to fix the higher user count issue:

Click on SMTP Configuration under the Server Configuration Menu. Next, click on the relay tab. Check the option reject emails for invalid users (See image below):


Either one of the following below:

  1. Use the Dynamic Recipient Verification. Please see this page for more details and instructions.

  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):