If you wish to use your own SMTP server for Email messages from the LogonBox server you can do this by first navigating to System Configuration -> SMS and Email.
Go to the Default Email Provider option and set this to SMTP. Select Apply to save this change.
Now navigate to Business Rules -> Messages -> Settings -> SMTP. You will now be able to provide the details of the SMTP server that you wish to configure for use by the LogonBox server.