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POP3 access failed inside Mail server


we have a Pop3 mail server 'A'inside our n/w.We can send and recv mails to any where,n o problem.but, we hv another mail se3rver 'B'in inside network.

mails destinated 'B'server thru 'A'Server could not be send.IN 'A'server message shows Mx lookup failed for IP X.X.X.X (global ip of 'B'Server)

i hv tried with alias command..anything available.

how can access an inside webserver from inside client by global ip or domain name

Community Member

Re: POP3 access failed inside Mail server

It looks like a subnetting and or routing issue from what you wrote? If your using 10.x.x.x as your inside subnet you will not be able to get to a 192.x.x.x subnet that resides inside the same physical segment as your 10.x.x.x subnet. Your clients will try to send it out your gateway and it will fail. If you have a router outside your gateway and an external dns server with the MX record there you could send the clients outside then back in. I would have to see a drawing of what you have set up to make sure I am on the right track with this. e-mail me offline at and I would be glad to take a look and see if I can help.


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