Solved

550 5.7.1 Unable to relay

Posted on 2008-09-29
12
1,216 Views
Last Modified: 2013-11-30
Remote users cannot send smtp email to users in other domains

If I configure John, a home user in Outlook 2007 using POP/SMTP John can send email's from home to any user in AD. But John cannot send email to other users outside the domain. If John log's on using OWA, John can send email to users in other domains.

If I enable "Allow messages to be relayed to these domains" under SMTP Connector Properties / Address Space it works as expected.

It appears the Outlook client is not authenticating. In Outlook 2007 I check "Log on to incoming mail server before sending mail". If I check "use same settings as my incoming mail server", outlook continuously prompts for username/password, all combinations fail to authenticate.

Note: We are using SBS 2003 with mydomain.local
0
Comment
Question by:joegrab
12 Comments
 
LVL 17

Expert Comment

by:Andres Perales
Comment Utility
One question I would have is why are you using POP / SMTP when you can setup and configure RPC over HTTPS?  Elimate having to have additional ports open in your firewall.
and he is entering his username and password for the domain correct?
has he tried, domain\username
and email address then password?
0
 
LVL 1

Author Comment

by:joegrab
Comment Utility
We are using RPC over HTTPS for "normal" remote users, unfortunutly I have a handful of MAC users and a few Outlook users (Doctor's) with primary exchange accounts in other domains.
0
 
LVL 1

Author Comment

by:joegrab
Comment Utility
Yes, I have tried username@domain and domain\username
In OWA the user credentials work fine.
0
 
LVL 12

Expert Comment

by:bhnmi
Comment Utility
If you already have OWA working you should just use RPC over http like stated above.

 http://www.petri.co.il/configure_rpc_over_https_on_a_single_server.htm
0
 
LVL 1

Author Comment

by:joegrab
Comment Utility
Because Outlook does not support two Exchange accounts in the same profile. These doctors require access to two exchange environments from the same Outlook profile. Why is the Outlook client failing to authenticate?
0
 
LVL 12

Expert Comment

by:bhnmi
Comment Utility
You can always mount the other mailbox into one or the others outlook profile.

You should check your IP address restrictions on the SMTP virtual server. It may be setup to only allow a certain range of IP's or set to deny access to address for relay other than the local subnet.
0
6 Surprising Benefits of Threat Intelligence

All sorts of threat intelligence is available on the web. Intelligence you can learn from, and use to anticipate and prepare for future attacks.

 
LVL 1

Author Comment

by:joegrab
Comment Utility
SMTP VC
Access/Relay - Only the list below
        - Grant 192.167.7.11 (Exchange Server)
        - 127.0.0.1
Allow all computers which successfully authenticate is checked
0
 
LVL 12

Expert Comment

by:bhnmi
Comment Utility
Some ISP's also require you to use their outgoing server when on their network. What is the ISP where this machine is located?
0
 
LVL 1

Author Comment

by:joegrab
Comment Utility
Why can I send to internal domain users and not users outside the domain.

Further testing, I can only send smtp to internal domain users if I select the bottom option in the Outgoing Server box in Outlook 2007 "Log on to incoming mail server before sending mail". Outlook 2003 just keeps poping up asking for username/password. The SBS 2003 server is configured with defaults, OWA work fine, Local outlook clients work fine, RPC over HTTP works fine. I just can't auth and send smtp eith a username/password.
0
 
LVL 1

Author Comment

by:joegrab
Comment Utility
Two Things

- Adding 192.168.7.0 (255.255.255.0) to the SMTP VC Access list fixed the problem for all remote users using SMTP.

- It appears the administrator account is somehow blocked in SBS 2003, Outlook test continues to prompt for username/password regardless of how you enter it. Entering any other username password combination works fine. Test message works and send to external user works fine.

I think bhnmi get's the points.
0
 
LVL 1

Accepted Solution

by:
ladydi711 earned 500 total points
Comment Utility
joegrab - you deserve points!    I have been pulling my hair out all morning testing sending email.  Can send fine from internal Exchange as well as OWA, but pop/imap with smtp would not....  BUT JUST WHEN USING THE Administrator account!  changing to any other user worked.  I have not found any other reference to that other than your post above  

"- It appears the administrator account is somehow blocked in SBS 2003, Outlook test continues to prompt for username/password regardless of how you enter it. Entering any other username password combination works fine. Test message works and send to external user works fine. "

THANK YOU THANK YOU!
0
 
LVL 1

Author Comment

by:joegrab
Comment Utility
I agree, the administrator bug was a real gotcha.
0

Featured Post

How does your email signature look on mobiles?

Do your employees use mobile devices to reply to emails? With mobile becoming increasingly important to the business world, it is in your best interest to make sure that your email signature looks great across all types of devices.

Join & Write a Comment

Resolve Outlook connectivity issues after moving mailbox to new Exchange 2016 server
Disabling the Directory Sync Service Account in Office 365 will stop directory synchronization from working.
To show how to generate a certificate request in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.:  First we need to log into the Exchange Admin Center. Navigate to the Servers >> Certificates…
how to add IIS SMTP to handle application/Scanner relays into office 365.

743 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

17 Experts available now in Live!

Get 1:1 Help Now