MDaemon 13.5.x: Why are remote users required to provide authentication when connecting?

Why do remote users have to provide authentication when sending email after I upgraded to MDaemon 12.5 and above?

For new installs of MDaemon 12.5 and higher, the IP Shield feature will be enabled by default and local IP address ranges will be added to the valid IP list. As a result, only those on the local network will be able to send messages using their MDaemon accounts. Remote users who are not providing authentication will not be able to send messages unless their IP address range is on the IP Shield list. 

To view the IP Shield settings, follow these steps in the MDaemon console:

  1. Click Security
  2. Click Security Settings 
  3. Select IP Shield 

These are the default entries that are added to the list: 


If you wish to disable the IP Shield feature, remove the check mark next to Enable IP Shield and then click Ok