Send HTML Email but Images Don't Go

 Hi, there,
 
I am trying to send an confirmation email after a user is created. I used
<MailDefinition BodyFileName="register.html"
                Subject="Registration Confirmation - Natarom Admin"
                From="services@domain.com"            
                IsBodyHtml="true" />
 
the email is sent with background color and texts, but images in an "images" folder are missing. Anyone has experience to tell me how to solve the problem?
Any help will be appreciated! Thanks!!
 
Ella
 
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