Configure Exchange 2003 to allow SMTP relay for an internal IP address

  1. Open Exchange System Manager,
  2. Navigate to:
    First Organization (Exchage) > Administravite Groups > Servers > [Exchange Server Name] > Protocols > SMTP
  3. Right click on SMTP Virtual Server > Properties
  4. Select “Access” tab and then “Relay”
  5. Add IP Address of internal IP address which requires the service.