Webmail problem

Hi!
I have a big problem. In the Starter Site Template error at:

 WebMail.Send(to: "email",
                        subject: "Please confirm your account",
                        body: "Your confirmation code is: " + token + ". Visit <a href=\"" + confirmationUrl + "\">" + confirmationUrl + "</a> to activate your account."
                        ) ;

It is the error message: 

The specified string is not in the form required for an e-mail address.

What is the problem???

Ben, Hungary :)