Hmm are you running windows 2003 btw? it only works in 2003..
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Browse All Topicsyesterday we started having problems with outgoing mail being stuck in the queue. the only message i get is "the connection was dropped due to an SMTP protocol sink". I've got 835 messages waiting to go out.
i tried everything that was recommended on this page:
http://forums.msexchange.o
but none of it seems to help the queue problem.
additionally i find this event disturbing:
Event Type: Warning
Event Source: smtpsvc
Event Category: None
Event ID: 2012
Date: 8/27/2004
Time: 12:56:29 PM
User: N/A
Computer: JUPITER
Description:
SMTP could not connect to the DNS server 'xx.xxx.xx.xxx'. The protocol used was 'UDP'. It may be down or inaccessible.
For more information, see Help and Support Center at http://go.microsoft.com/fw
Data:
0000: d5 04 00 00 ...
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am running windows 2k3, ran the dnsdiag as suggested:
C:\WINDOWS\system32\inetsr
Running in debug/verbose mode.
The DNS flags are not explicitly set in the metabase, assuming default flags - 0
x00000000
These are the local IP addresses (server-bindings)
xx.xxx.xx.2
Microsoft Exchange is installed on this machine.
Querying domain controller for configuration.
The domain controller server which will be used for reading configuration data i
s jupiter.xxxx.com
Connecting to jupiter.xxxx.com over port 389
configurationNamingContext
This will be used as the Base DN for all directory searches.
Checking if the target server mail.xxxx.com is an Exchange server
Searching for an Exchange Server object for mail.xxxx.com on the domain
controller
No Exchange Server object found for mail.xxxx.com on domain controller,
mail.xxxx.com is an external server (not in the Exchange Org).
Checking on DC if the VSI being simulated is configured with external DNS server
s.
Searching for an Exchange Server object for jupiter.xxxx.com on the doma
in controller
LDAP search returned some results, examining them.
Examining next object for attributes we are interested in.
Successfully read the distinguishedName attribute on the Exchange Server object.
The value of the attribute is CN=JUPITER,CN=Servers,CN=P
tive Groups,CN=GSP,CN=Microsoft
eting,DC=com
The search returned the following 6 values for the networkName attribute for the
Exchange Server object for jupiter.xxxx.com
Attempting to match the TCP/IP networkName of the Exchange Server object returne
d from the domain controller against the FQDN we are searching for
0> networkName: ncacn_vns_spp:JUPITER...ma
1> networkName: netbios:JUPITER...match failed
if there is a glaring problem there i can't see it. i have tried both external and internal dns servers. the outgoing mail still doesn't work.
Were any changes made to the firewall or router recently?
Have you tested DNS with NSLOOKUP? http://support.microsoft.c
Have you tested SMTP with telnet? http://msexchange.org/tuto
Do you have multiple NIC's in the machine ... have you checked the hardware lately?
If you use Queue Viewer, and click on the queue where the messages are stuck does it provide any other information?
I'd try turning up logging on MSExchangeTransport and see what other errors are generated.
Is the Exchange server also a DNS server? Are you using Root Hints, forwarding queries to another server, using an internal caching server?
Like most of the others stated ... I agree, DNS is most likely the culprit ...
i've re-installed the internet dns servers. there was a problem there. one of the server somehow got corrupted. the exhange server is not a dns server. the dns servers are very standard.
i've since tested dns with nslookup. it seems fine.
but now i'm getting this error:
Event Type: Error
Event Source: smtpsvc
Event Category: None
Event ID: 2013
Date: 8/28/2004
Time: 4:58:48 PM
User: N/A
Computer: JUPITER
Description:
SMTP could not connect to any DNS server. Either none are configured, or all are down.
For more information, see Help and Support Center at http://go.microsoft.com/fw
Data:
0000: 7c 26 00 00 |&..
both network cards are working perfectly. i can browse the network and internet with either unplugged.
i have the MSExchangeTransport logging. all i'm getting is a lot of this:
Event Type: Information
Event Source: MSExchangeTransport
Event Category: SMTP Protocol
Event ID: 7512
Date: 8/28/2004
Time: 5:04:55 PM
User: N/A
Computer: JUPITER
Description:
The message with ID <200408282127.OAA89807@mai
For more information, click http://www.microsoft.com/c
also i get this error when i set an outside dns server
Event Type: Warning
Event Source: smtpsvc
Event Category: None
Event ID: 2012
Date: 8/28/2004
Time: 5:17:09 PM
User: N/A
Computer: JUPITER
Description:
SMTP could not connect to the DNS server '65.106.1.196'. The protocol used was 'UDP'. It may be down or inaccessible.
For more information, see Help and Support Center at http://go.microsoft.com/fw
Data:
0000: d5 04 00 00 ...
Can you ping that external DNS server from the Exchange server?
It is starting to look like your firewall isn't allowing DNS traffic to go out correctly. DNS is still a problem.
Try a nslookup test from a command window.
That last message "Rejected/Deleted by Intelligent Message Filter" indicates that the remote site is running Exchange 2003 with the new IMF that was introduced along side SP1 for Exchange. Your message has scored highly as spam and has been deleted - or your domain is on their blacklist.
These types of things don't happen for no reason - someone must have changed something or you have a piece of hardware about to fail.
Simon.
Windows 2003 will act as a good email relay.
Install a new copy of Windows 2003 and add the SMTP service. Then configure it to accept email for your domain, then add the IP address/dns name to forward email to your Exchange server.
You could also look at using something like GFI Mail Essentials to work as the gateway server. You need to check that the new relay machine can do dns lookups as well - that it isn't getting the same UDP errors that the other machine is getting.
Simon.
setting up a new relay server didn't work. instead of all the individual queue getting this "the connection was dropped due to an SMTP protocol sink" message just the queue to the relay server was.
at this point i'm going to try to re-install service pack 1. thinking there's some corruption in the exchange install. i too believe something has changed on the network though nothing i can trace.
Business Accounts
Answer for Membership
by: Yan_westPosted on 2004-08-27 at 11:25:03ID: 11916124
When you are investigating possible DNS issues, I would suggest you download the DNSDiag.exe tool on ownloads/d etails.asp x? FamilyID =E0F616C6- 8FA4-4768- A3ED-CC09A EF7B60A&di splaylang= en.
http://www.microsoft.com/d
Its called DNS Resolver Tool. You can test out resolution to domains using a
syntax like dnsdiag mail.foo.com -d -v 1, and it will show you the query to
the DNS server as batched by Exchange in verbose mode and possible errors.