Question : Mail from our exchange server gets rejected by recipient mail servers that perform reverse DNS check

The server in question is a Windows Server 2003 Small Business Server with exchange.  Currently it sends and recieves email just fine unless mail is sent to a host that performs reverse DNS lookup and then the email gets rejected.  I have had the ISP make a reverse DNS record for mail.ourdomain.com on there DNS server.  Still when I perform the reverse DNS test on mxtoolbox.com it comes Failed to lookup xx.xxx.xxx.xxx IN-ADDR.ARPA, I have replaced the actual IP with Xs.  I am not an expert at DNS and would appreciate any help in this matter.  Thank you in advance.

Answer : Mail from our exchange server gets rejected by recipient mail servers that perform reverse DNS check

If your SBS server will be providing DNS you will need to create a Reverse lookup zone for your mail server's IP.  Open DNS> rightclick reverse lookup zone> New Zone

As an example, If your mail server's IP was 192.168.120.5 you would create a reverse zone called 120.168.192.in-addr.arpa
Once the zone is created you would right click on zone and choose new Pointer(PTR).  For the host IP number just put the last digit of the IP, in this example 5.  in hostname put mail.yourdomain.com

Your ISP should be set up to point to your DNS server