ISP will not add PTR reverse dns record!!

My SBS 2003 server was earlier running on XO communications which I now switched to Time Warner. Hence I needed to setup my email server once again. After doing the same many of my sent mails are not getting delivered and are coming back to me. I guessed the problem would be due to PTR hence I called up Time Warner and requested them to install a PTR for myserver.mydomain.com point to our static public IP. But in response they said they dont do PTR records or reverse lookup zones.

So I wanted to know from you guys what can I do now to fix the issue. Can I just add these records to my DNS server? Please provide some help.

Yes, even I think the cause is PTR and only your ISP or TW can add the same. I don’t think there is anything else from your side to fix this issue. You cannot do anything from your server. The only alternate I guess you can do is using their mail server as a smart host to try to avoid the lack of a PTR record for your IP. See if it helps. By the way is this a business class service from Time Warner that allows you to run your own mail server?

As the reverse zone is controlled by your ISP address block I don’t think you would be able to use your own server to host the reverse zone. However there some (less number of) ISPs who may delegate a portion of the zone to you which allows you to host your own reverse DNS,see if your ISP is one of them.

It is not compulsory that your public IP has no rDNS entry only if they won't set up a custom PTR for you. Do one thing, just try pinging -a xxx.xxx.xxx.xxx. The mere presence of a PTR is generally enough to pass muster.

I've just called TimeWarner and they setup the PTR record on the phone. Actually they were very nice about it.