Subscribers dont receive emails

Hello.

Just downloaded the “Email Subscribers & Newsletters” plug in. I have set up widget and published a subscription form on a page and entered a test mail. However when I send a newsletter according to your guide “How to Create and Send Newsletter Emails” the email dont come through. For your information I have checked spam etcetera but so I know the email has not come through correctly.
I am a bit rooky here and really dont know where what the problem might be. Please help me to give me suggestions on how to solve this problem

Thank you!!