[Mailman-Users] some users recive email but they can't send

Hello,

I have a problem with a user of a list that I create. She receive all the list emails but she can't send emails. She recive this error response:

Remote host said: 554 <chile-datos@mail.degu.cl>: Relay access denied

I think that is strange because other users have no problems sending emails to the list.

-- Regards,

Daniel H.