unable to send mail to a specific domain, pretty sure its exchange

Do you see any emails stuck in the queue? if yes.. on which queue are they stuck?
do you have a smart host configured ? ISP ? try to remove that and put  DNS for troubleshooting point of view and then restart the smtp & routing engine service and see if that works..

do nslookup on the command prompt...what dns server does it show ?
it shoud be internal
do :
nslookup
set q=mx
remotedomain.com

does it show the MX ?

--> do telnet maila.microsoft.com 25
ehlo

what ip address do you get near ehlo command ??? let me know... i will check if you are black listed

-xsam

x-sam
i see 34 emails in the queu for @oursistercompany.com, i right clicked and said force connection, the numbers have not changed

ino idea about smart host configured? what is that

isp? what are you asking exactly here

"try to remove that and put  DNS for troubleshooting point of view and then restart the smtp & routing engine service and see if that works.."

i have no clue what this statement even means


DNS request timed out.
    timeout was 2 seconds.
*** Can't find server name for address 192.168.1.203: Timed out
Default Server:  UnKnown
Address:  192.168.1.203

> set q=mx
> mcsen.com
Server:  UnKnown
Address:  192.168.1.203

DNS request timed out.
    timeout was 2 seconds.
*** Request to UnKnown timed-out


250-mail01.microsoft.com Hello [65.90.195.130]
250-SIZE 10485760
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-STARTTLS
250-AUTH
250-8BITMIME
250-BINARYMIME
250 CHUNKING

Does the email domain for the other company exist anywhere in your Exchange configuration? Ie would it make Exchange think the domain is local rather than remote?
If so then you need to make some changes to Exchange as you are sharing the SMTP address space.
http://support.microsoft.com/kb/321721

-M

the email domain exists at their location, off network

You have a DNS Problem...

cos when i do nslookup i get the following :


Non-authoritative answer:
mcsen.com.co.in canonical name = com.co.in
com.co.in       MX preference = 0, mail exchanger = com.co.in

com.co.in       nameserver = ns40.hostgator.com
com.co.in       nameserver = ns39.hostgator.com
com.co.in       internet address = 67.18.199.2
ns39.hostgator.com      internet address = 67.18.199.2
ns40.hostgator.com      internet address = 67.18.199.3

-x

now try this...
nslookup
set q=mx
server 4.2.2.2
mcsen.com

what do you get now ?

try the nslookup the one you did above and now on the dns server itself too..
and let me know the results..

-x

You are not blacklisted.. i conformed it.. so no need to worry about that..
let me know the results...for the above...

-x

i had to attach screen shot, sorry i could not copy between my pc and the gotomypc
screenshot.1235760369.jpeg

here is the screenshot from the DNS server
screenshot.1235760474.jpeg

go to your dns server... open dis console...
peroperties of your serve there... forwarders tab--> check if the ips mention there are ALIVE... it shoud be your ISPs dns server IPS. contact your isp and get the latest IPS.
also add 4.2.2.2 and 4.2.2.3 in there.--> ok
now right click on the server again.. and clear the cashe.. and restart the dns...
on the command prompt... do ipconfig /flushdns and register dns--> on exchange and also your dns server...

now try to do nslookup and see the difference...

-x

On both the server make sure the network binding should be set correctly...

network connection window.... on the top click on advance00advance settings... your nic which is enabled should be on the Top

-x

i still get the timeout from the exchange to the dns as soon as i run nslookup

this seems to also be affecting @yahoo and @aol and a few other domains, but those queue sizes are not as large as our sister company's

also

the exchange server itself is setup for a static ip, but its primary dns server is pointing to the dns server on our network

there should not be any external dns server on the NIC.. primary or secondary...
do you get the same time out whn you do the nsllookup on the dns server itslef?

no it returns localhost 127.0.0.1 right away with no issues

i did some more searching, apparently on teh DNS server i did not have a reverse lookup for our network created (192.168.1.x), so i created one

it still times out

i got diffrent results when running the nslookup from my home laptop

all 3 are diffrent

dnsserver.jpg
mailserver.jpg
homelaptop.jpg

configured dns server with public dns servers
created new forward
new queue is still building up
queue.jpg
forward.jpg

nic bindings are also set properly

Thanks x-sam
i think you were on the right track but our soulution was a little unique, instead of using the SMTP connector to the fortitude.concentric.com i added our mail server provided to us by our isp (see we use a pop3 downloader to get all of our mail in the first place) once i configured the SMTP connector to go there, everything started going through like gold.

good. Thanks for sharing ;-)

-xsam