DNS confusion... my problem or theirs?

[jbraly]

Another school in my town gets the message below when trying to send an

email to us, or when replying to an email from us...


I do get external emails from people from many different ISPs
successfully (just not from them) ... Likewise, they are successful in
sending emails outside their network to any other ISP(Example, they
were able to send an email to my personal email account)... but anytime

THEY send an email to MY MAIL, they get the error message below:


______________________________­_______________
From: System Administrator
Sent: Thursday, April 21, 2005 2:05 PM
To: lastname, firstname
Subject: Undeliverable:RE: test


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


Subject: RE: test


Sent: 4/21/2005 2:05 PM


The following recipient(s) could not be reached:
firstname, lastname on 4/21/2005 2:05 PM
The destination server for this recipient could not be found in Domain
Name Service (DNS). Please verify the email address and retry. If that
fails, contact your administrator.
<mailcat.trinity.msft #5.4.0>


I am wondering if this has ANYTHING to do with me or him...
He is replying to the email i send, but the odd thing is that emails
they send out to ANYONE else go out fine... likewise, I get external
emails all day long from many different ISPs, just not his...


I have a seperate server running "GFI Mail Essentials" that scans mail
for viruses and spam, then forwards it to my email server...


My mail server is exchange 5.5 SP6a


i replaced my name with firstname lastname


thanks in advance

 

[Kevin D. Goodknecht Sr. [MVP]]

Another school in my town gets the message below when trying to send
an

email to us, or when replying to an email from us...


I do get external emails from people from many different ISPs
successfully (just not from them) ... Likewise, they are successful in
sending emails outside their network to any other ISP(Example, they
were able to send an email to my personal email account)... but
anytime

THEY send an email to MY MAIL, they get the error message below:


______________________________­_______________
From: System Administrator
Sent: Thursday, April 21, 2005 2:05 PM
To: lastname, firstname
Subject: Undeliverable:RE: test


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


Subject: RE: test


Sent: 4/21/2005 2:05 PM


The following recipient(s) could not be reached:
firstname, lastname on 4/21/2005 2:05 PM
The destination server for this recipient could not be found in Domain
Name Service (DNS). Please verify the email address and retry. If that
fails, contact your administrator.
<mailcat.trinity.msft #5.4.0>


I am wondering if this has ANYTHING to do with me or him...
He is replying to the email i send, but the odd thing is that emails
they send out to ANYONE else go out fine... likewise, I get external
emails all day long from many different ISPs, just not his...


I have a seperate server running "GFI Mail Essentials" that scans mail
for viruses and spam, then forwards it to my email server...


My mail server is exchange 5.5 SP6a


i replaced my name with firstname lastname


thanks in advance

You say they are replying to an email?
What is the email address used in the reply to section of your email?
It sounds to me like the reply address is not in the correct email address
format (e-mail address removed)

 

[jbraly]

If it helps at all, my email filtering server (Mail Essentials by GFI)
was sending me an email every hour over the weekend saying things like:

"The following checks failed when testing your DNS functionality:
DNSRBL check
SPF check

It is suggested to check that your DNS server is functioning
correctly."

But this morning, im getting none of these messages, I am getting
emails form the outside world and I am able to email out... but still
have not gotten a responce from that other school...

Thanks in advance.
Jazzmann