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npanprome

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unable to receive email from certain people

Dear Experts,

We are using Microsoft Exchange Server 2003 SP2, for the passed 2 weeks
we got a call from our customer said they are unable to send email to us
but we can send email to them

they receive the bounce back email said

Router: Failed to connect to SMTP host UNICAL.COM because : SMTP Protocol Returned a Permanent Error

today I got a notice from another user saying the same error, they both using Lotus Note as thier email server

Please advice,

Thank you
Natt
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Stacy Spear
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What was the error code?
Is your domain unical.com? If so there seems to be a problem with your MX record.

http://zmailer.org/cgi-bin/mxverify-cgi?DOMAIN=UNICAL.COM+&SUBMIT=SUBMIT+KV9.FI+NETWORK

Doing resolver lookup for T=MX domain=``UNICAL.COM ''
ERROR: NO SUCH DOMAIN: ``UNICAL.COM ''
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npanprome

ASKER

Dear mass2612,

my domain is mail.unical.com but that error is from my customer email, I can receive mail from all other people except only this 2 right now unable to receive any email

Dear darkstar,

I didn't receive any error code on my customer email all the email me on my alternate email is
-------------+----------------------------------------------------------------||  
ຠ   |   Router: Failed to connect to SMTP host UNICAL.COM because :  ||             |   SMTP Protocol Returned a Permanent Error                    
||-------------+----------------------------------------------------------------|  

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   bú†„6ö   v¨Í‡öŒ ¨ïå*ddö1W1J   ‚œÍ‡ö1W 160°„1W1J   d^¨60vÖö1W1J &G‡öò“Ÿ0@      vÖ„6ö

MPDCS2/MPDC, MPDCS2/MPDC, MPDCS1/MPDC
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mass2612
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Dear mass2612,
I try using your website to test my email domain it said I don't have postmaster?
" Eh ? What ? No ``postmaster'' supported there ? That violates RFC 2821 section 4.5.1. "
and
"Something WRONG!! rc=451"

what is that mean? where do I check my postmaster?
Please advice,

Thank you
Natt

Dear mass2612,

Yes! last 2 week before this happening we change our ISP from telepacific to time warner
do I have to call them to check my mx record?
I would guess that your IP changed also I would definately give them a call and ask them to check everything out as although it can take sometime for the DNS change to be replicated around the world it probably should only take a max of 48 hours. Check your MX, reverse DNS records.
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I agree that whoever is your ISP/ provider and setting up your DNS stuff needs to make the corrections so that DNSstuff.com report shows it is OK.

Otherwise you will continue to have all sorts of weird issues.


I hope this helps !
General rules for switching ISPs:

1) Register a test domain on the Internet
2) Set up Domino to accept this domain
3) Set up an additional test Domino server with a test mail account on it
4) Point the t est domain MX at the test server
5) Try using GMAIL to send a message to your corpoarte address and the test acocunt address on this test domain.  If it fails, you may need to wait up to a couple of days for DNS propagation
6) Set up yur second ISP without terminating your first ISP
7) Place the test server on the new IP, without taking it off the old one.  Make sure it has both IP addresses.  If you are NAT'ed, then this is no big deal -- server only needs one address, but both NATs point to the test box.  Note that NATs can make steps 3 and 4 complicated, because you will need two IPs from yoru ISP that go to your NAT router, and the NAT router has to process them differently. Most SOHO routers can't handle this, so you'll need either a "real" router, or an extra SOHO router for the second IP... and in this case, the third IP
8) Reconfigure your MX to point to the new address
9) Re-test sending, but use Yahoo this time, so that you know it is not aching the MX (since you Yahoo has never sent to this domain).  See what path it came in on.  Should be the new IP.  If not, keep working at it until it gets the new IP, you may need to use a different webmail service for each retry to avoid DNS caching issues.
10) WHen it is all working, apply all the things you learned about the test domain to set your main Domino server to receive on both ISP's IP addresses, use the testdomain to see that the main Domino server can receive on the new IP, and finally switch your production domain form the old IP to the new IP and test that it works.
11) Wait a week, verify that everything is coming in properly on the new IP and only the new IP, and cancel the old service

All in all, expect to have at least 7-10 days of overlapping service