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Adam F
Adam F, System Administrator
Category: Networking
Satisfied Customers: 87
Experience:  Microsoft Exchange 2003/2007, MCP, Windows 2003/2008 AD/DHCP/DC, Desktop Support, Server Support.
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Why cant i send email from my exchange server to gmail accounts

Customer Question

Why can't i send email from my exchange server to gmail accounts?
Every time i try to send a message to any gmail account, the messages get returned with the following:
Your message did not reach some or all of the intended recipients.

Subject: Web Design by Netricks
Sent: 12/7/2010 5:47 PM

The following recipient(s) could not be reached:

[email protected] on 12/7/2010 5:47 PM
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.

We are not listed on any RBLs that I know of. I have checked on

That is all.
Please help if you can. Thank you


Greg [email protected]
Submitted: 6 years ago.
Category: Networking
Expert:  Lindie-mod replied 6 years ago.


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Expert:  Christopher Bessler replied 6 years ago.
This really sounds like a rule setup on the Exchange server. Blocking all accounts.

Unless other accounts in this environment CAN send to GMAIL accounts...

Let me know...
Customer: replied 6 years ago.
No rules are setup that I know of. I used to be able to send to gmail. It just recently stopped working. Do u want to login and look at my exchange box?

I just figured that gmail uses some special rbl or something like that.

Thank you

Expert:  Adam F replied 6 years ago.

Let me introduce myself. Names Adam, I am MCSA, MCTS: Exchange 2007 and MCITP: Enterprise Messaging Admin for Exchange 2010.

Now that I got that across, have a few questions:

1) Are you sending this through Outlook, OWA, ActiveSync?
2) What is the domain name in question
3) Have you attempted to use SMTPDiag (free download from Microsoft) to test this?
4) Are you only using a hub transport server or an Edge Transport server within a DMZ?

If you need help with step #3 I can guide you to the download. If I can see the output from the SMTPDiag test, I can further assist you and provide a proper answer.
Customer: replied 6 years ago.

Thank you for the reply.

I have tried sending from Outlook, OWA and my iphone. Akll act the same way and bounce any message to a account.


My exchange server is I have it running through spam filtering.


I have not tried SMTPDiag.

I will try it. Ill be at the office in about an hour.


I am not in a DMZ.


This is the exact message i get.

Your message did not reach some or all of the intended recipients.

Sent:12/13/2010 10:14 AM

The following recipient(s) could not be reached:

[email protected] on 12/13/2010 10:14 AM
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
< #5.5.0 smtp;550-5.7.1 [ 7] Our system has detected that this message is likely>


Thanks again for your help.


Greg Richburg

Expert:  Adam F replied 6 years ago.

Now on to how to properly use SMTPDiag, just in case you are unable to find the download or use it.


SMTP Diagnostic tool (free from microsoft) is a tool designed to send a "test" smtp message from your organization to an outside organization. It will provide verbose output to tell us where it failed (DNS errors usually; mx, soa, ect).


You can download SMTPDiag from here:


Its a small download that will go on the Exchange server. You will extract the SMTDiag.exe file (its a command line based tool) to your desktop, and then move it to the root of the C:\ drive.


What you want to do next is open a command line and run the following commands:


1) CD C:\ (or whatever directory you moved the SMTPDiag file to)

2) smtpdiag [email protected] [email protected]

3) press enter and paste the output here.


Now, you are obviously going to change the [email protected] to a real email, and same with the gmail.


I will also need to know more about your archtecture of your exchange env. as asked above.


Thanks again,



Expert:  Adam F replied 6 years ago.



Thank you for the information. You are just using a hub transport server correct?

Do you receive SMTP Error 5.7.1 for any other recipients? How many users within this Exchange organization are unable to send email to the fqdn?


Reason I am asking is because SMTP Error 5.7.1 is a "unable to relay" error message.

You may want to check the hub transport settings as described here:


You may also want to check the settings on the spam filter and whitelist * as an acceptable sending domain.





Customer: replied 6 years ago.

Cool, Thanks, XXXXX XXXXX do that when i get there. My network is simple.

SBS 2003 server

Comcast Business ISP with the modem in bridge mode. Then I have a linksys router. Simple switch and 8 windows PCs and 1 linux and i mac box.


I run avira business class antivirus. Nothing else fancy. Business apps, thas all.


No one in my network can send to gmail accounts.



Expert:  Adam F replied 6 years ago.



When looking into this further I will really need to see the SMTPDiag to get any further.

I looked into your spam filter as all your MX records point there, and that seems proper. No RBLs on any of them (checked through mxtoolbox).


Wierd part is this. I attempted to telnet on port 25 to the ip address in the NDR, and it fails. This might be from firewall rules/settings, but if I cannot do a EHLO test, then there is little I can do from here.


The 5.7.1 message shows you are unable to relay. Look at the send connectors on the hub transport server and make sure your spam filter settings on MX Guarddog are configured correct.


When you post the SMTPDiag output I will be able to further assist.

Customer: replied 6 years ago.

It all of a sudden started working again. I did not do a darn thing.

WTF?!? haha

Thanks for the tips on SMTP Diag.

I ran that and it looks good...

So i then tested my email again and it now goes through.


Customer: replied 6 years ago.

Now i teswted again today and it is failing again.

Smae error

Customer: replied 6 years ago.

i ran Smtpdiag again and got the same results as before. Exactly.

Any suggestions?





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