Link to home
Start Free TrialLog in
Avatar of steviekz
steviekzFlag for Australia

asked on

Can send but cannot receive on Exchange Server 2007 SP3

Hi All,

I recently installed Exchange Server 2007 SP3 (64BIT) on my Windows Server 2008 R2 (64BIT) System.

After configuring the Exchange Server, I find I can Send emails without any problems, however, I cannot Receive.

Logged into my Mailbox (OWA) and sent an email to my Hotmail Account. Once received, I replied. Navigated back to OWA and cannot see any emails from "Hotmail". I have checked to see whether all of my "Port Forwarding" have been configured correctly;

•      PPTP TCP/UDP 1723 1723
•      L2TP TCP/UDP 1701 1701  
•      POP3 TCP/UDP 110 110
•      SMTP TCP/UDP 25 25  
•      Telnet TCP/UDP 23 23
•      FTP TCP/UDP 21 21  
•      HTTPS TCP/UDP 443 443
•      HTTP TCP/UDP 80 80
•      RD TCP 3389 3389
•      SSMTP TCP/UDP 587 587
•      SMTPSSL TCP/UDP 465 465
•      SMTP587 TCP 587 587  
•      LDAP TCP/UDP 389 389
•      UDP TCP 500 500  
•      SPOP TCP 995 995
•      TLS TCP/UDP 143 143
•      PPP TCP 146 146

I also ran a utility called "Email Address Verification ( and ended up with the following message:

Mail server found for domain
- (priority 10, ip address:
Error connecting to mailserver:
 No route to host

Another utility which I ran was the Microsoft Exchange Remote Connectivity Analyser and ended up with the following error:

      Testing inbound SMTP mail flow for domain
       ExRCA failed to test inbound SMTP mail flow.
      Test Steps
      Attempting to retrieve DNS MX records for domain
       One or more MX records were successfully retrieved from DNS.
      Additional Details
      Testing Mail Exchanger
       One or more SMTP tests failed for this Mail Exchanger.
      Test Steps
      Attempting to resolve the host name in DNS.
       The host name resolved successfully.
      Additional Details
      Testing TCP port 25 on host to ensure it's listening and open.
       The specified port is either blocked, not listening, or not producing the expected
        Tell me more about this issue and how to resolve it
      Additional Details
       A network error occurred while communicating with the remote host.

I understand that Port 25 is blocked and did run another utility called "Port Checker" (done online) and stated that my Port 25 on my WAN IP is blocked.

What would be the best course of action?

Thanks guys!!

Avatar of Tony J
Tony J
Flag of United Kingdom of Great Britain and Northern Ireland image

Check the firewall on the server and ensure port 25 isn't blocked.

It sounds like it may be getting through your firewall.

Also - do a quick telnet to it from the external address. If you get something such as **********20********20****** then it may be that the firewall isn't recognising the protocol properly.
Check SMTP port as Tony1044 sais. If have open this port, call to your ISP because some ISP filter some traffic for security reasons.
Avatar of steviekz


Thanks guys for the answers!

I have performed "telnet 25" and find it cannot open the connection to the host (I performed telnet on a different network or ISP (Mobile Internet Sharing))

The firewall on the Router and Server have been turned off to determine what is causing the issue. However, I'm still not having any luck.

What would you guys think?..

Thanks again!!

Ask to your ISP
Hi Drashiel,

Already did. They advised that Port 25 is blocked, however, is there another way of receiving emails?
Do you have a RECEIVE Connector configured for Port 25 for ALL external IP Addresses ( - excluding your internal IP Range) with TLS Authentication enabled and Anonymous Permissions enabled?
Hi alanhardisty,

Yes, I have two receive connectors. The first receive connector is labled as "Default" and the Port Number is set to 25. The FQDN is set to "server.domain.local" (Server Full Name or Computer Full Name)

The remote IP addresses are from

TLS, Basic Authentication and Exchange Server Authentication are checked under the "Authentication" Tab. Permission Groups:

Anonymous Users
Exchange Users
Exchange Servers
Legacy Exchange Servers

The second Receive Connector, Client Server, has the FQDN set to "" with Port 587 and with the following Remote IP Addresses:

Authentication are set as follow; TLS, Basic Authentication and Integrated Windows Authentication.

The Permission Groups are set as follow;

Anonymous Users
Exchange Users
Exchange Servers
Legacy Exchange Servers


Okay - a bit generous with Authentication / Permissions on the Default connector, but at least it covers the basics needed.

Have you got Anti-Virus / Anti-Spam installed?  If so - what?
Nope, no Anti-Virus or Anti-Span installed. I also have my Firewall turned off till I find out what is causing the Exchange not to be able to receive emails.

Are all exchange (Automatic) services started?

Can you run the following from a command prompt and post the results please:

netstat -anbp tcp | findstr :25
But your ISP is blocking port 25. Are you not on a business class connection?

Does your ISP have a smarthost you could connect to?
User generated image
Nope, I'm on a Home Plan. Not sure, however, I can contact Optus and ask hoping that they will have a Smarthost

There are, of course, other solutions of this type. This was the second in the list for Googling "what to do if port 25 is blocked by my isp"
Thanks Tony1044!

However, that service offered by AuthSMTP is only for Sending not receiving. Correct me if I'm wrong...

Avatar of Tony J
Tony J
Flag of United Kingdom of Great Britain and Northern Ireland image

Link to home
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
If you visit on the server - does the response match the IP Address configured for your MX record?

If not - sounds like you are on a Dynamic IP Address and thus Tony1044's comment of setting up a DynamicDNS Address is highly appropriate.
Yeah, even sending can be problematic on a dynamic IP - because of spam, IP blocks in dynamic address ranges are often arbitrarily bocked.
WooHoo! It's working!!

Thank you Tony1044 and to all those who helped!

Basically I registered for "Dyn Email Gateway" and typed "" as the Destination Address followed by the Relay Port: 587.

Now I can send and receive emails without any problems!

alanhardisty, I'm using "Dyn Updater". It is a service offered by DynDNS which updates my Hostname to the WAN IP Address (Dynamic IP).

Thanks guys!!
Excellent - glad you are working.  Well done Tony.
Keep it up guys! This website is by far the best (in my opinon)

Glad it's working, and appreciate your comments, however you need to take some of the credit too. Your original post contained plenty of useful and pertinent information and you provided quick and positive answers to questions and guidance.

Believe me, it makes all the difference and makes things an order of magnitude easier to deal with.

Good luck with it and don't hesitate to holler if you run into any more issues.
Avatar of k94ss01

HI folks,

QQ. for the 2007 experts...I just recovered my 07 mail stores, but even though I recreated and  verified my inbound smtp receive connector, no matter what I do, I can no longer the the mail server to open a port 25 listen, thus get relay errors from my external (to host..inside my lan) spam server.  trying to telnet port 25 just keeps getting "Connecting To not open connection to the host, on port 25: Connect failed" errors.  I tried deleting and rebuilding the connector to no avail..I did however notice this onthe mail flow troubleshooter:

Server exchange2007 has the Hub Transport server role and the following services are not started:  MSExchangeTransport. These services need to be running for mail to flow properly, then noticed my Transport service shutting down..then found this in the event viewer:
The Microsoft Exchange Mail Submission Service is currently unable to contact any Hub Transport servers in the local Active Directory site. The servers may be too busy to accept new connections at this time.

This is the last hurdle to server recovery for me, and I'm finally stumped..

k94ss01 - If you have a problem you will be more likely to get help by asking your own question rather than posting in a question that is 3 years old.

A new question will attract all the available experts.  Posting in this question will only attract only the experts already in this question (3 Experts only).

No problems - just want to make sure you get as much help as possible.
just posted on main..hopefully get some replies..this one's got me leaving forehead indent on desk :)