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Thread ID: 63442	2005-11-09 23:26:00	"Unable to deliver" email messages	Billy T (70)	Press F1

Post ID	Timestamp	Content	User
403016	2005-11-09 23:26:00	Hi Team I have been getting occasional email delivery warning messages, like the first one below, when sending messages to one or two addresses within NZ, one in Australia and (most commonly) several in the US. I put it down to a problem with my privately hosted email and domain name server perhaps not meeting all the correct security protocols, and found that resending via my Xtra account usually got through. Yesterday I discovered that a major client had been trying unsuccessfully to send me an email message for several days but had been getting similar "undeliverable" messages. This was a major concern, so I immediately moved my domain and email to Orcon. This was a planned move anyway because the private host was taking the server out of service soon and did not intend to replace it. As far as I can tell the transfer went smoothly and all services are operational from my point of view, with emails apparently arriving as normal. Trouble is, you never know what wasn't delivered!! Warning Message 1 (for email sent via old server/host) ********************************************** ** THIS IS A WARNING MESSAGE ONLY ** ** YOU DO NOT NEED TO RESEND YOUR MESSAGE ** ********************************************** The message you sent: Date: Fri, 4 Nov 2005 08:28:28 +1300 To: "**********" <******62@bigpond.com> Cc: Subject: RE: Equations Has not yet reached the following recipient(s): *********62@bigpond.com The mail server will continue to try and deliver it for 3 days I think that the above message finally went through because I haven't received a final failure message and the three days are up. I have never had any problems sending to this address in the past. Warning Message 2 (for email sent last night via Orcon) ********************************************** ** THIS IS A WARNING MESSAGE ONLY ** ** YOU DO NOT NEED TO RESEND YOUR MESSAGE ** ********************************************** The original message was received at Wed, 9 Nov 2005 20:54:31 +1300 from 219-88-**-**.jetstream.xtra.co.nz ----- Transcript of session follows ----- ... while talking to extmail.bigpond.com.: >>> MAIL From:<**my domain name**.co.nz> SIZE=1621 <<< 451 Mail from this IP address blocked due to DNS block list. <*******@bigpond.com>... Deferred: 451 Mail from this IP address blocked due to DNS block list. Warning: message still undelivered after 4 hours Will keep trying until message is 5 days old Can anybody enlighten me as to what could cause these refusals? So far they have only affected the one address in Australia (though I don't send to many over there) and a range of addresses scattered throughout the States. What worries me and prompted me to post on the issue was the problems my client had in sending to me. Hopefully that is resolved by the change to Orcon but I still haven't received the message!! I am also baffled as to why bigpond.com would block Orcon's DNS. Cheers Billy 8-{) :confused:	Billy T (70)
403017	2005-11-10 00:01:00	Have you tried e-mailing/phoning orcon & asking them about this? & have you e-mail bigpond.com? About this as well ( as they may tell you why orcons dns are blocked)	stu161204 (123)
403018	2005-11-10 00:32:00	Have you tried e-mailing/phoning orcon & asking them about this? & have you e-mail bigpond.com? About this as well ( as they may tell you why orcons dns are blocked) No, not yet Stu, I am seeking backgound advice and knowledge here first so that I know what I am talking about. Bigpond is the one that concerns me most, because it has given delivery problems for messages from two entirely different email hosts. I do forsee potential problems emailing them via my new host when they can't deliver, but I have always got yahoo and freenet account options I can use. I'll not bother Orcon until I have something more definite to work with. Cheers Billy 8-{)	Billy T (70)
403019	2005-11-10 00:34:00	They may be comparing your A record, PTR record and your host name reported during the smtp greeting, for antispam purposes. Eg: You server says it's "mail.billyt.co.nz" in the SMTP greeting. The system looks up A record for mail.billyt.co.nz and it returns 219.88.34.24 The system looks up PTR record for 219.88.34.24 and gets "219-88-34-24.jetstream.xtra.co.nz" when it should really get "mail.billyt.co.nz" The example above is for Xtra, but the same thing may apply to Orcon. You can either get the person who manages the DNS for your net block to create a valid PTR record for your IP (if you have a static IP), or else you could configure your system to relay off a SMTP smart host at your ISP rather than having your mail server attempt direct delivery (the smart host should have matching A and PTR records).	BIFF (1)
403020	2005-11-10 20:20:00	Thanks Biff, that was the sort of insight I was looking for. I had a complete failure to even send for a large PPT file last night, but didn't have time to investigate so I just resent via Xtra. I'll try another send this morning and come back to this thread if I get any more clues. Cheers Billy 8-{)	Billy T (70)
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