Jump to content


 


Register a free account to unlock additional features at BleepingComputer.com
Welcome to BleepingComputer, a free community where people like yourself come together to discuss and learn how to use their computers. Using the site is easy and fun. As a guest, you can browse and view the various discussions in the forums, but can not create a new topic or reply to an existing one unless you are logged in. Other benefits of registering an account are subscribing to topics and forums, creating a blog, and having no ads shown anywhere on the site.


Click here to Register a free account now! or read our Welcome Guide to learn how to use this site.

Photo

SMTP issues on Server 2012


  • Please log in to reply
4 replies to this topic

#1 hispaladin

hispaladin

  • Members
  • 245 posts
  • OFFLINE
  •  
  • Gender:Male
  • Location:Middle of a corn field
  • Local time:04:54 AM

Posted 22 January 2016 - 11:00 AM

I have a windows 2012 server that has SMTP setup on it to email scanned documents from our company scanner to our employees.  We use office 365 and do not host Exchange in-house anywhere so all email sent is going outside the network.  The trouble that I am having is every time we scan a document I get the following error

 

Message delivery to the remote domain '********.com' failed for the following reason: Unable to bind to the destination server in DNS. 
 
The really strange part is that the email does eventually send but it takes between 10 minutes and sometimes hours before it will send.  This causes no small amount of productivity issues when people need the documents they scanned.  I have searched with google and everything I can come up with points to Exchange.  Any ideas on what I could check into to figure this out???  As far as I know every email that is sent goes to the same domain as the scanner is the only thing that is used.  We recently switched servers from a windows 2003 server to the 2012 server and the 2003 server did not have the issue.
 
Hispaladin


BC AdBot (Login to Remove)

 


#2 Demonslay335

Demonslay335

    Ransomware Hunter


  • Security Colleague
  • 3,527 posts
  • OFFLINE
  •  
  • Gender:Male
  • Location:USA
  • Local time:04:54 AM

Posted 22 January 2016 - 11:10 AM

Is that a bounce-back, or where is that error recorded? The error makes me think something is goofy with DNS. Check your MX records particularly. There is also the possibility you are getting relay issues if you don't have the proper PTR records publicly, since your server is just relaying email to Office 365.

 

You can also try testing SMTP by using telnet on port 25 (assuming defaults). You can lookup how to talk SMTP protocol and see if you are getting a funny response.


logo-25.pngID Ransomware - Identify What Ransomware Encrypted Your Files [Support Topic]

ransomnotecleaner-25.png RansomNoteCleaner - Remove Ransom Notes Left Behind [Support Topic]

cryptosearch-25.pngCryptoSearch - Find Files Encrypted by Ransomware [Support Topic]

If I have helped you and you wish to support my ransomware fighting, you may support me here.


#3 hispaladin

hispaladin
  • Topic Starter

  • Members
  • 245 posts
  • OFFLINE
  •  
  • Gender:Male
  • Location:Middle of a corn field
  • Local time:04:54 AM

Posted 22 January 2016 - 11:36 AM

The error that I am seeing is in event viewer on the server, source is smtpsvr.  I am looking into the DNS, just found that something may be off with our external DNS servers, more exactly which ones we are pointing too.



#4 hispaladin

hispaladin
  • Topic Starter

  • Members
  • 245 posts
  • OFFLINE
  •  
  • Gender:Male
  • Location:Middle of a corn field
  • Local time:04:54 AM

Posted 22 January 2016 - 01:37 PM

OK, solved the issue.  We have two DCs on the network and the old SMTP server was pointed at the first DC and the new is pointed at the new DC.  The problem was that the two DCs were not pointed at the same external DNS servers.  Fixed that and all is good again.

Thanks for the reply DemonSlay



#5 Demonslay335

Demonslay335

    Ransomware Hunter


  • Security Colleague
  • 3,527 posts
  • OFFLINE
  •  
  • Gender:Male
  • Location:USA
  • Local time:04:54 AM

Posted 22 January 2016 - 01:40 PM

Yay DNS. Glad you got things figured out with a slight nudge in the right direction.  :thumbup2:


logo-25.pngID Ransomware - Identify What Ransomware Encrypted Your Files [Support Topic]

ransomnotecleaner-25.png RansomNoteCleaner - Remove Ransom Notes Left Behind [Support Topic]

cryptosearch-25.pngCryptoSearch - Find Files Encrypted by Ransomware [Support Topic]

If I have helped you and you wish to support my ransomware fighting, you may support me here.





0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users