[Exim] exim-3.13-1 on Red Hat Linux 6

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Hi All :

I have a mail server here running Red Hat Linux , using exim-3.13-1.
We have a client who is using someone else for their incoming POP3 mail ,
but for their outgoing SMTP mail , they are pointing to my mail server.
I assumed for lack of better knowledge that this requires me to permit relaying
for their domain and local IP address ranges , and I did that. I have not set up this
domain as a local domain , only as a relay domain.

The strange thing is that our clients can send and receive email from an external
address , but they cannot send email to each other in the same office for the same
domain. For example , janet@??? can send to someone@???
and receive from that email address , but janet@??? cannot send internally
to bob@???. No error messages are being reported , but the mail simply
does not get sent to the intended recipient.

From a general mail configuration perspective , does anyone have any ideas on what
could be causing this ?

Any help or advice much appreciated

Regards , Jason



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