this is my serial monitor :
220 smtpcorp.com Esmtp Exim 4.85 Sun,03 May 2015
250-smtpcorp.com.Hello [14..100.132.123]
250-SIZE 52428800
250-8BIMIME
250-AUTH CRAM-MD5 PLAIN LOGIN
250-STARTTLS
250HELP
500 unrecognized command
334 VXN1 cm5hbwu6
334 UGFzc3dvcmQ6
501 INVALID BASE 64 DATA
500 unrecognized command
221 smtpcorp.com closing connection
disconnected
Email failed