Вытащил лог:
An error occurred while processing the outgoing e-mail message with subject "111 CRM:0001169" for SMTP:
http://vm-crm-test:5555/ServiceDesk for delivery through pigeonedgesrv.ecotrust.local. System.Net.Mail.SmtpFailedRecipientException: Mailbox unavailable. The server response was: 5.7.1 Unable to relay
Щас попробуем настроить эксчейндж