At least one recipient does not have an email address or is marked as "Do Not Allow" email.

Hi everyone,

Firstly, I apologize for my inadequate English.  I get such an error while trying to send a contact mail to  in crm 2013.

I'm sure the contact's email addresses is right and email permission allowed. 

(My CRM's language is turkish) İzin Verdi= Allow

What should I check, thanks in advance for your support.