Telnet to Port 25 on new Exchange 2007 Server

Hi all,

Hopefully someone can assist.

I have recently set up a new Exchange Server within my network.  I am able to send out email from the server quite fine.

I have not amended any of my MX records as yet to point to my static IP address from my ISP.  All I am trying to do at the moment is telnet via port 25 to my box (to test connectivity prior to changing the MX records).

At first I thought it was issues with my Netcomm modem, not having the port forward set up correctly.  After much playing around I installed PFPortChecker from, shut down the exchange services and tested on the server whether the port forward works.  PFPortChecker came back and said everything is fine and the port is open.

I can telnet to port 25 using the internal IP address, and the Exchange SMTP component seems to work fine, however when telneting on the external ip address from the ISP it does connect.

I have contacted the ISP, and they also confirm that from their side port 25 is open, but they also cannot connect.

My external static is

I am pretty new to 2007 so I could be missing something fairly easy.  Firewall has been turned off on the Server, as well as the client machines that I am using to perform tests.

Any help would be greatly appreciated.

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Manpreet SIngh KhatraSolutions Architect, Project LeadCommented:
Have you created the Host A record andd try to get the MX record and then try telnet.
jason_willisonAuthor Commented:
Hey Rancy,

Not too sure what you mean?

All I am trying to do is to Telnet to on Port 25

At this point in time I'm not making any MX record changes as I want to ensure that telnet does work from outside in.

Manpreet SIngh KhatraSolutions Architect, Project LeadCommented:
Tilll the time we do not have a host entry at the ISP how would telnet find the IP entry on INternet ?
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jason_willisonAuthor Commented:
Can't you just type the following:

telnet 25

Or am I missing something here?
Below is what i got after telnet 25

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Manpreet SIngh KhatraSolutions Architect, Project LeadCommented:
And Aihaiai if you hit ehlo after that what do you get, do you see the verbs
jason_willisonAuthor Commented:
Hi all,

Thanks for the help.  It seems that I cannot telnet in to the IP address from my internal network.  Tried from a different ISP and all is sweet.

Thanks, much appreciated.
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