Thanks for the help in advance! I have a new SBS 2003 R2 Standard setup and I am having issues with very random NDR's when sending mail. I can't for the life of me figure out the common denominator!

 

System Setup:

 

1 Loaded Dell Poweredge 2900 SBS 2003 R2 STD Box (All updates applied)

1 Dell Poweredge 1650SC Terminal Server running Windows 2000 Server

8 XP Pro Clients

2 Windows 2000 Pro clients

 

2 NIC's (Intel not Broadcomm)

Static IP

Router

 

Using POP3 Connector temporarily

Sending using smarthost (could be my problem)

 

RWW, VPN works great...So my IPCONFIGS should be good. I'll post if needed.

 

My problem is that my users (all) randomly get the following NDR:

 

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

      Subject:  RE: Some Text
      Sent:     9/25/2007 1:49 PM

The following recipient(s) could not be reached:

      Jedd Clampett on 9/25/2007 1:49 PM
            The e-mail address could not be found.  Perhaps the recipient moved to a different e-mail organization, or there was a mistake in the address.  Check the address and try again.

           

 

For example I got 7 NDR'S total on 09/25/2007 from 4 different users. It seems that the problem usually occurs on a reply, but not always. Event logs are all clean as a whistle.

 

I setup a smarthost to my companys ISP for sending mail and the POP3 connector for receiving mail using smallbizserver guidelines. I really don't understand why I set up a smarthost, I just tried it when configuring CEIW wizard and it seemed to work. My smarthost is smtp.knology.net. Would it be better to use DNS to send my mail and if so would it help to fix the NDR problem?

 

Thanks,

 

Tony

Update:

 

I changed the sbs box to use DNS as opposed to a smarthost...in the last 3 hours I have not recieved any NDR's, crossing my fingers that this change fixed the issue with the random NDR's. If I do not get any NDR's in 24 hours I will assume the issue is fixed.

Update:

 

Using DNS did not fix the problem...4 bounces since my last post! Help....

I'm still in need of help with this problem...Any takers?

 

I have tried to rebuild the Recipient Update Services (enterprise Config) and now I receive 3 per day as opposed to 7 - 13. Should I rebuild both Updates Services (Enterprise Config) and Update Services (Mydomain). I did not rebuild my domain, just the enterprise configuration.

 

Thanks,

 

Tony

Tony,

 

From which domains do you receive those NDR's? The problem with some servers is that they send out NDR's but there not really NDR's but a way to fool spammers. If that is the case you have to ask those domains to stop doing that.

Mariette -

 

Thanks for the reply! The NDR's come form random Domains, I can't find a common denominator, except that the NDR always happens when a user either reply's to a message in the inbox or if they forward a message. If the user resends the message it almost always delivers without a hitch. The bounce is always instantaneous.

 

Tony

Hmmm, kind of an odd problem and difficult to troubleshoot if there is no pattern. The only thing that I can think of is a flaky smart host or DNS server. Where is that smart host?

The smarthost I WAS using was my ISP's, smtp.knology.net, however, thinking it maybe a smarthost problem I switched to DNS to send my email (via the SBS CIEW wizard). After switching to sending mail via DNS the problem got better, 4 - 7 NDR's versus 7 - 14 using the smarthost. So far today I only see one NDR, crossing my fingers that the NDR numbers keep going down. I'm still using the POP3 connector to get our email from our hosting service (different than our ISP) but will switch completely to DNS shortly.

 

HTH,

 

Tony

Mariette -

 

Sorry, if you mean physically where is the smarthost at, that would be Hunstville Alabama...

 

Tony

Tony,

 

If it constantly fails then I suspect a flaky DNS or smart host. I really have no other ideas then that. Can you use another smart host? Not from the same ISP but some other ISP?

Update: 07/16/2008

 

Problem solved...

 

It took forever but I think we finally solved this issue. I'm not exactly sure what fixed the problem but one or a combination of the steps below stopped the problem.

 

Tip: Turn up Diagnostic logging on Exchange Server when having ndr issues...

 

1.   Ran Isinteg (found corruptions) with Antivirus turned off.

2.   Ran a second time to make sure the database returned no errors.

3.   Added exclusions to Kaspersky Antivirus to prevent file level scanning of several exchange related files.

See: http://www.smallbizserver.net/Forums/tabid/53/view/topic/postid/92070/forumid/8/tpage/1/Default.aspx

I had most of these excluded, but the edb.chk file was getting scanned and I was not aware that several edb.chk files exist, so I did a wildcard to get them all.

4.   A very recent exchange update on the server via WSUS. I seriously doubt that this had any effect, but I can not rule out this update as a reason for the lack of random ndr's.

 

Thanks for your help and I hope this helps Admins with similar problems!

 

Tony