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HomeHomeUsing DNN Platf...Using DNN Platf...Administration ...Administration ...SMTP email not sending to internal addressesSMTP email not sending to internal addresses
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7/22/2013 2:17 PM

I recently became IT Manager for a company that uses DotNetNuke to manage its ebusiness website. Users have informed me that for about six months, they have not received notification emails for orders, customer quote requests, or registrations. 

I hopped on the site admin and updated the emails to correct person in our office, but quickly realized there was a technical issue with its configuration when I didn't see test emails going through. 

I started troubleshooting and in the process I have configured the host and portal administrator accounts, set up the SMTP to our mail server, set up a receive connector in Exchange that allows mail to relay from the ebusiness site, and tried dozens of configurations of user names and passwords as well as anonymous in the SMTP settings. 

I've currently got it configured to send through the SMTP server via anonymous. My test email says that it sends successfully, but I actually don't know where to check that.

I am able to send newsletters to my personal gmail account, but not my email address. If it is configured as such, can receive quote notifications to my gmail account. Here is the error I get when trying to send a newsletter email to my work address:

System.Net Error: 0 : [0560] Exception in the SmtpClient#22695746::Send - Mailbox unavailable. The server response was: 5.5.4 <[email protected]>... Mailbox does not exist.
System.Net Error: 0 : [0560]    at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify, SmtpFailedRecipientException& exception)
   at System.Net.Mail.SmtpClient.Send(MailMessage message)
System.Net.Sockets Verbose: 0 : [0560] Socket#40139210::Dispose()

Why would it return "Mailbox does not exist" for my domain email address, but send it successfully to my personal email? 

I've gotten quite the education searching through the many DNN forum posts, but seem to be completely stumped and without even a working hypothesis for this one. Let me know if you have any ideas. 

New Post
7/23/2013 7:28 PM

Hi Adam ~

The test email should send TO the email of the administrator account for the site. If it is not received there, that is a problem. You might try changing that email address (the admin users) just for a test to see if you can receive it at an account outside the problem domain.

Often times there is a filter in your mail server that won't permit it to process mail that it thinks might be an impersonation. The anonymous send would probably trigger that... make sure that the SMTP User / Password & SMTP Server are legit... as well as the email account of the Admin user. Your email servers SMTP  log should give you some feedback.


Scott Willhite, Co-Founder DNN

"It is only with the heart that one can see rightly... what is essential is invisible to the eye. "
~ Antoine de Saint-Exupéry

New Post
7/24/2013 8:52 AM

Thanks Scott.

Just to clarify, the administrator of the site would be the email under Admin -> Users -> admin, correct? 

Now that I know where the test email is supposed to go, I think I'll troubleshoot that first before I go any further.


New Post
7/24/2013 10:26 AM

Setting the host email and the admin email to my personal account returned a successful SMTP test to my personal account through the company SMTP server with anonymous as the setting. Now I need to get this to happen through the company email.

Curiously, if I change the "Host Email" setting under Host Details to my company email address - which as I understand, should send an email to my personal email account (set as the administrator user) from my company email address, I get the error

There has been an error trying to send the test email. The error is:
Mailbox unavailable. The server response was: 5.5.4 <[email protected]>... Mailbox does not exist.</[email protected]>

What could this indicate?

New Post
7/24/2013 1:39 PM
It Looks as an issue with the Mailserver configuration and/or DNS Settings.  Contact you the mailserver as localhost or with the or ?  It could be that you must enable relaying on the mail Server for the IP !
HomeHomeUsing DNN Platf...Using DNN Platf...Administration ...Administration ...SMTP email not sending to internal addressesSMTP email not sending to internal addresses

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