In order to send a test mail, please take the following steps:
go to campaigns > open a campaign
open an email template
Click preview template in the bottom right corner
Click send a test email in the top right
The test mail will be sent via the mailing account of the user who is logged in
Before sending the email, google chrome will show a drop-down menu where you will be asked as follows: 'do you want to send a test email to' followed by your email address.
If the email address is correct, click go ahead and click ok.
Please note: The test mail can only be sent if your campaign has already been populated with prospects.