[Mailman-Users] Undelivered Mail Returned to Sender

Hello people!

I have just installed Mailman and I am getting an error everytime I send an email to the list. The error is:

<"|/usr/local/mailman/mail/mailman post whb-ventas"@bw-ip-34.dnsba.com>
(expanded from <whb-ventas at webhostingboulevard.com>): Host or domain name
not found. Name service error for name=bw-ip-34.dnsba.com type=A: Host not
found

Any suggestion will be appreciate!

Thanks in advance,
Pablo