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Last Error: 450 Client host rejected: cannot find your hostname, [83.96.34.42]

F_A_H_D
F_A_H_D asked
on
hi all

i cannot send out to some domains when im opening the message details in queue viewer in my exchange 2010 i can see the error
 Last Error: 450 Client host rejected: cannot find your hostname, [xxx.xxx.xxx.xxx]

the internal mail server name is different than the DNS record i configured in NetworkSolution
on network solution is mail.domain.com
and in the actual server name is servername.domain.com

i configured my internal DNS to have MX record for mail.domain.com and it points to ip of servername.domain.com

to save your time i connected to PC out of the network and with different ISP and i run the following

C:\Users\Administrator>nslookup mail.domain.com
Server:  localhost
Address:  127.0.0.1

Non-authoritative answer:
Name:    mail.domain.com
Address:  xxx.xxx.xxx.xxx


C:\Users\Administrator>nslookup xxx.xxx.xxx.xxx
Server:  localhost
Address:  127.0.0.1

Name:    servername.domain.com
Address:  xxx.xxx.xxx.xxx

is the problem because of the revers ?????????

or what ??
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AkhaterSolutions Architect
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Commented:
This is because you don't have a PTR in the reverse lookup zone for the IP you are sending from
Solutions Architect
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Commented:
you have to ask your ISP to  create a PTR record for you pointing 83.96.34.42 to mail.domain.com

Commented:
what is your PTR record for your domain.

Commented:
ahehehe... forgot to refresh.. lol

as advised by the 2 master above. :)

Author

Commented:
this is the reply i got from the ISP

Dear Fahd,
            Kindly note it is recommended for any “PTR” record to match its “A” record, so we modified your IP reverse record as requested:
 
> set q=ptr
> xxx.xxx.xxx.xxx
Server:         62.215.6.5
Address:        62.215.6.5
xxx.xxx.xxx.xxx.in-addr.arpa        name = mail.domain.com.
 
Kindly note that any DNS modification takes 3-24 hours to be updated globally.


so what he done is correct ?

Author

Commented:
and how i can test if what he did is correct or not
should i run
nslookup xxx.xxx.xxx.xxx


and it should point to mail.domain.com   .... am i correct ???
AkhaterSolutions Architect
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Commented:
Yes this is what you should do you did it well

for the test you cannot do it from inside your network you will need to do it from a computer connected to the internet

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