One or more mailboxes associated to the email server profile {0} have been disabled for sending email because a server certificate ...

One or more mailboxes associated to the email server profile {0} have been disabled for sending email because a server certificate that is required to connect to the email server using SSL could not be validated. Make sure that a valid certificate is installed for Microsoft Dynamics CRM to connect to the email server. Then, enable the mailboxes for sending email.