Problems With Email Pilots

Hello. Well, i cant send any email for my pilots.

I get this erros ( is send to administrator email)

Mail delivery failed: returning message to senderâ€

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its

recipients. This is a permanent error. The following address(es) failed:

junior_arrabaca@hotmail.com

Mail sent by user nobody being discarded due to sender restrictions in WHM->Tweak Settings

------ This is a copy of the message, including all the headers. ------

I try send for one pilot,two, all and i get this erro. Plis help…

Thanx!

Looks like you need to authenticate with your mail server, that is the error.

I use Cpanel, where i can authenticate my mail server?? Thanx!

Who’s your host?