To use Gmail as your SMTP server, first, you need to turn on the 'Access for less secure apps' setting within your Gmail account. This allows external systems (such as Campus 365) to interface with your account. To learn more and change this setting, go to google.com/settings/security/lesssecureapps.
If you see a notice that 2-Step Verification is turned on but can’t use this setting, you need to generate an app-specific password to integrate with Campus 365. Do so by going to security.google.com/settings/security/apppasswords.
Once you've done whichever step is relevant to your Gmail account, fill in the Email Domain fields with:
  • Email Engine: SMTP
  • SMTP Username: Gmail Email Address (The address you want these emails to come from)
  • SMTP Password: Gmail Account Password
  • SMTP Server: smtp.gmail.com
  • SMTP Port: 587
  • SMTP Type: SSL
Test SMTP Settings
Go to ERP > Communication > Send Email to test the email settings. To send a test email using the customized SMTP settings, choose the recipient from the "Email To" column.

Note:  Depending on your service provider, it would be advised that you remove the restriction of sending emails from an unauthenticated sender. Please contact your SMTP provider to ensure this can be done.
In order to stop fraudulent activity, many free email services (including Google, Hotmail, and Yahoo) forbid using additional email names. This issue also exists for domains using Google Apps for email. 
You can create email accounts on that SMTP server and edit them directly from addresses if you have an SMTP service provider account (typically included as part of commercial web hosting).