Email Unsubscribed - CDO

Hi All,

I want to send email from CDO records through custom object data services "Send Mail" process steps.

So, In the CDO has one Email Field, the mail will be sent to that field.

My Question : If the Email Address is "Globally Unsubscribed" means, won't allow to send mail to that email address. But, right now the mail was sent.

How to restrict the mail services.

Please Urgent.