Undelivered Mail Returned to Sender

Buenos días, tenemos problemas de correo con varias direcciones de destinatarios:

This is the mail system at host relayout03.dominioabsoluto.net.

I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can delete your own text from the attached returned message.

                   The mail system

<xxxxxxxxxxxxxxxxxxxxxx@cpenedes.com>: host aspmx.l.google.com[173.194.66.26] said:

    550-5.1.1 The email account that you tried to reach does not exist.

Please

    try 550-5.1.1 double-checking the recipient's email address for typos or

    550-5.1.1 unnecessary spaces. Learn more at 550 5.1.1

    http://support.google.com/mail/bin/answer.py?answer=6596

ib3si328615wjb.48

    - gsmtp (in reply to RCPT TO command)