Can't email form Exchange

[julesNDC]

I can’t get my email server to send emails to some email addresses. 90% of emails are going out without a problem but for some reason some specific domain names don’t work and one of them are Hotmail accounts. I had the ISP setup a reverse DNS lookup on the IP to mach the Domain name but that did not make any difference.

It looks like emails are leaving the server and 2 to 5 minutes later they are back into the Queue.

It has to be something stupid that I can’t see.

Thanks for your help.

 

[nsantin]

Your are describing a reverse DNS problem.

your rDNS record must match the FQDN of your mail server, not just your doman.

Goto the properties of you SMTP connector for your server. Goto "Delivery" -> "Advanced" options. make sure the name you set in the FQDN field matches your rDNS record. Typically you would call somrthing like "MX1.DOMAIN.COM" or "MAIL1.DOMAIN.COM" etc. Then have your ISP create the rDNS record with that name.

You should also check it by testign your domain at:

http://www.dnsreport.com

(do a DNS test and look at the mail record results)

 

[julesNDC]

Thank you for your help. Here is what I found out do far.

- The FQDM filed matches my DNS record
- The ISP did create the (4 days ago) the DNS record with that name
- When I run the DNS Report form

http://www.dnsreport.com

I get one error (red). The error is below.


ERROR: One or more of your nameservers reports that it is an open DNS server. This usually means that anyone in the world can query it for domains it is not authoritative for (it is possible that the DNS server advertises that it does recursive lookups when it does not, but that shouldn't happen). This can cause an excessive load on your DNS server. Also, it is strongly discouraged to have a DNS server be both authoritative for your domain and be recursive (even if it is not open), due to the potential for cache poisoning (with no recursion, there is no cache, and it is impossible to poison it). Also, the bad guys could use your DNS server as part of an attack, by forging their IP address. Problem record(s) are:




Any ideas?
Thanks