Go to 360Suite's Administration Console.
Go to Technical.
Fill the SMTP configuration with your SMTP server information without selection an SSL option.
Fill your username and password.
Try to send a test email to verify your configuration.
A warning appears : SEN015
The connexion to a Microsoft SMTP server (like Exchange) with credentials on a non-secured channel (SSL/TLS disabled) is not supported by the JavaMail library used by the application to send emails.
Switch to a secured communication channel by enabling the SSL/TLS option in the SMTP configuration of the application, and change the SMTP port used accordingly.
Please note that your SMTP server must support SSL/TLS encryption.
Remove the credentials from your SMTP configuration, to avoid passing credentials over the network on a non-secured channel. This is only possible if your SMTP server accepts connections without credentials.