Error al recibir correos

[mauroshek]

Buenas tardes les agradeceria mucho me pudieran ayudar con este error, solo sucede cuando mando correos a cualquier cuenta con @dominio.com.co desde mi red local la cual tiene un servidor de dominio igual, dominio.com.co.

Las cuentas de correo se usan a travez de google apps.

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: 550 550-mail-ey0-f173.google.com [209.85.215.173] is currently not permitted to
550-relay through this server. Perhaps you have not logged into the pop/imap
550-server in the last 30 minutes or do not have SMTP Authentication turned on
550 in your email client. (state 14).

Gracias.