Search Again: Re: Windows and QuickDNS From: Aaron Lynch Date: Wednesday, June 6, 2001 Time: 3:30:35 pm On 6/6/01 2:31 PM, The Defendant "Men & Mice Support" <cbuxton@menandmice.com> Confessed: > At 1:02 PM -0400 6/6/01, Dave Cooper wrote: >> Hi, >>=20 >> After recently tightening security on our mail server, all of my Windows >> boxes (Win95,98,2000) are unable to send mail to the mail server. The e= rror >> message indicates that the reverse DNS look is returning a different nam= e, >> etc. My Macs are ok. Does QuickDNS 2.21 work with Windows? If so can = you >> offer any hint as to what isn't set up in my configuration? >=20 > Your mail server is misconfigured. It should accept any and all mail > from local machines. >=20 > That oversight appears to be combining with a lack of PTR records for > your Windows machines. Who controls your PTR records, you or your > ISP? If you're on a private subnet, with a NAT server, then the > answer is you, by definition. I would take this a step farther. If you are bouncing mail based on a PTR record not matching up, your mail server is misconfigured, and is explicitly violating the RFC. (there was a thread about this on the Communigate list) RFC1123: ----------- =A0=A0=A0=A0=A0=A05.2.5 HELO Command: RFC-821 Section 3.5 =A0=A0=A0=A0=A0=A0=A0=A0=A0The sender-SMTP MUST ensure that the <domain> parameter in a =A0=A0=A0=A0=A0=A0=A0=A0=A0HELO command is a valid principal host domain name for the =A0=A0=A0=A0=A0=A0=A0=A0=A0client host. As a result, the receiver-SMTP will not have to =A0=A0=A0=A0=A0=A0=A0=A0=A0perform MX resolution on this name in order to validate the =A0=A0=A0=A0=A0=A0=A0=A0=A0HELO parameter. =A0=A0=A0=A0=A0=A0=A0=A0=A0The HELO receiver MAY verify that the HELO parameter really =A0=A0=A0=A0=A0=A0=A0=A0=A0corresponds to the IP address of the sender. However, the =A0=A0=A0=A0=A0=A0=A0=A0=A0receiver MUST NOT refuse to accept a message, even if the =A0=A0=A0=A0=A0=A0=A0=A0=A0sender's HELO command fails verification. -- Aaron Lynch System Administrator NineWire Digital Solutions || http://ninewire.com If I ever get real rich, I hope I'm not real mean to poor people, like now. -Jack Handy

Messages In This Thread: Windows and QuickDNS by Dave Cooper on Jun 6, 2001 at 10:02:47 am Re: Windows and QuickDNS by andrew on Jun 6, 2001 at 10:27:52 am Re: Windows and QuickDNS by Men & Mice Support on Jun 6, 2001 at 2:33:14 pm Re: Windows and QuickDNS by Aaron Lynch on Jun 6, 2001 at 3:30:35 pm Re: Windows and QuickDNS by Men & Mice Support on Jun 6, 2001 at 4:03:36 pm Re: Windows and QuickDNS by Dave Cooper on Jun 6, 2001 at 5:30:35 pm Re: Windows and QuickDNS by Dave Cooper on Jun 6, 2001 at 5:37:11 pm Re: Windows and QuickDNS by Men & Mice Support on Jun 6, 2001 at 9:55:57 pm Re: Windows and QuickDNS by Dave Cooper on Jun 8, 2001 at 8:36:47 am Re: Windows and QuickDNS by Men & Mice Support on Jun 8, 2001 at 9:50:57 am Re: Windows and QuickDNS by Sam Narayanan on Jun 10, 2001 at 12:35:08 pm Re: Windows and QuickDNS by micaelac on Jun 11, 2001 at 6:08:00 pm