[exim] No Incoming Mail

I have been reading the Mailing list archives and googling for over 12 hours
and I am sure it is a simple detail I am missing.

I can connect to the exim4 server with a smtp client from a remote box and
send mail anywhere. To the local users and to users on different servers
(ie: gmail). However when I respond to those emails from gmail, the mail
never gets delivered, there are no errors in any of the logs, and gmail
never mentions anything like message not delivered. I can also send mail
from the localhost locally and to gmail.

What can I do to continue troubleshooting this error? I am out of ideas to
search for.

Why would the server or gmail not even recognize that there is a problem?
There is no sign of mail delivery failures in any of the logs on the server.

Any ideas?

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dc_eximconfig_configtype='internet'
dc_other_hostnames='flagfuels.com'
dc_local_interfaces='127.0.0.1;64.22.109.24;64.22.109.239'
dc_readhost=''
dc_relay_domains=''
dc_minimaldns='false'
dc_relay_nets=''
dc_smarthost=''
CFILEMODE='644'
dc_use_split_config='false'
dc_hide_mailname=''
dc_mailname_in_oh='true'
dc_localdelivery='mail_spool'
===============================