buenas tardes , me esta marcando esto cuando mando a algunas direcciones de email ,ya que con otras no tengo problema, uso sendmail
An SPF-enabled mail server rejected a message that claimed an envelope sender address of victorv(a)aagjc.com.mx.
An SPF-enabled mail server received a message from mail.aagjc.com.mx (189.254.21.4) that claimed an envelope sender address of victorv(a)aagjc.com.mx.
However, the domain aagjc.com.mx has declared using SPF that it does not send mail through mail.aagjc.com.mx (189.254.21.4). That is why the message was rejected.
If you are victorv(a)aagjc.com.mx:
aagjc.com.mx should have given you a way to send mail through an authorized server.