AOL Blocking emails sent from my server!

[undrop79]

Hello,

I've been having a problem for while since we upgraded our company's server to Win2003 SBS standard.

We use Exchange 2003 which is included in Win2003 SBS to send and receive everyones emails within the organisation but it seems that whenever we try to reply or send a new email to a client with an AOL account, the message gets returned to us with the following:

Undeliverable:SUBJECT
System Administrator

Your message did not reach some or all of the intended recipients.

Subject: SUBJECT
Sent: 25/05/2005 22:50

The following recipient(s) could not be reached:

james@aol.com on 27/05/2005 23:02
Could not deliver the message in the time limit specified. Please retry or contact your administrator.
<theburlingtonhotel.com #4.4.7>

I'm aware that AOL has some kind of Spam Blocking system (Black Book) which may be the cause of this error, but how do I get unblocked from it??

I'm still unaware of whether it is our domain name 'theburlingtonhotel.com', our web & email hosts '1and1.co.uk', our ISP 'Plus.net' or our own physical server which is located in the organisation running exchange 2003 which has been blocked!

The strange thing is that if I bypass our exchange server to send the email with one of my personal email accounts, 'christian @ isawyouonthedancefloor.com' (Also hosted by 1and1.co.uk) the email goes through fine. Which would mean that it's not an issue with our ISP, but probably with our own server.

We have a very basic setup due to our needs and I am the "Administrator" per-say, in that I set-up the network to save the company some cash and get up-to-date. Any advice (in layman's terms) would be really appreciated...

[nottheusual1]

Hi,

Common problem with Exchange. Start here:

1. Be sure your mail server has a reverse DNS entry.

2. Be sure your DNS record has an SPF TXT entry (Sender Policy Framework) Look here for more info:

http://spf.pobox.com/

3. If your organisation IP address (where the server is located) is a dynamic IP address, like from SBC or RoadRunner, it will be blocked - reason is that many of the zombie machines out there that spam the h3ll out of the aol domain are on dynamic IP's, so they don't allow mail originating from them.

Normally, if they've BL'd you, you get a different reject response with a link that explains such. I don't believe this is the case in your situation.

[brian.mark]

You said "within the organization". Does this mean that your mail server is in your building? If so, that may be the problem. We had a mail server on our LAN for a while, but since the IP address we were hitting was a private address, AOL refused email since it couldn't talk to the IP address of the server we sent it from. We had to change the mappings so that our mail clients talked to the public address of the web server, then it worked fine.

Also, with the reverse DNS mentioned by nottheusual1, your ISP is most likely going to have to set that up. You're not going to have authorization to provide reverse DNS unless you're going to a level 1 provider directly, and then normally only if you have at least a class C block of IP's. It's up to the upstream provider to issue RDNS responses.

Brian.

[undrop79]

Thanks for your responses. They've just proved to me that I know nothing about how exchange and mail servers operate, because I think I only roughly understand what you are saying... :o(

From what I can work out, what's happening is this. The domain "theburlingtonhotel.com" is registered with my Webiste Host's mail server which is where the 'MX Records'? are located (don't even really know what they are). Anyway, when users at my organisation try to send mail, the SMTP used is our own server to which "theburlingtonhotel.com" is not registered and so AOL sees it as being spam because in theory my server does not have the right to send emails using this domain name. Only my Host's SMTP servers are allowed to.

Which is why, when I tried to send an email externally to an AOL user, routing the SMTP in outlook for chris@theburlingtonhotel.com to route through auth.smtp.1and1.co.uk instead of via my exchange server, it seemed to work. Hence the problem IS with our server which, as brian.mark stated, is in our building.

Nottheusual1, I'm not sure how to check if my mail server has a reverse DNS entry. I had a look on the internet and am guessing it's by opening my Default Virtual SMTP Server in Exchange system Manager, right click Properties dialog box, on the Delivery tab, click Advanced and then check the box "Perform Reverse DNS lookup on incoming messages"?

Had a look at what you mentioned about an SPF TXT entry and looked at http://spf.pobox.com/ - Very interesting stuff and what they say about me getting a lot of spam from myself or even users who dont even exist on my domain happens quite often to me too. So it could be this, but I can't quite understand what it asks for on the wizard (again going back to MX records etc) :o( Sorry, I'm sure I mentioned my knowledge of Exchange is basic to non existent...

My Server has a private IP 192.168.16.xxx as advised by Microsoft, and we have a static IP supplied by our ISP Plus.net on our DSL connection which provides internet access to the rest of the users through a router connected to a secure gateway and then directly to our server.

Brian.mark, I can speak to my Hosting company to find out more info about setting up the reverse DNS, and the class C block of IP's and RDNS responses? No idea what they are but they should I suppose.

How did you setup your change the mappings so that your mail clients talked to the public address of the web server?

Really sorry about the EXTREMELY long post, just want to make sure that I'm including everything I've done so that I don't waste peoples time too much...

[brian.mark]

Just point the SMTP server setting in your mail client to the external IP address.

To see if you have a reverse DNS (RDNS) entry, just click start / run / enter "cmd" and hit enter. Now, type in "tracert XXX.XXX.XXX.XXX" where the X's are your IP address. For example, for mine it's "tracert 12.109.80.230" and I see one of the first responses as "Tracing route to www.toolbarn.com [12.109.80.230]". If you don't get a name, no RDNS entry has been made. It's usually best if you try this from outside of your own network, though.

In many cases, using your ISP's SMTP server is better. If you use their outbound, you can still use your own email address from your site. They just allow you to send via their server since you're their customer. You can still receive via your server and just send via theirs. That's how quite a few web hosts tell you to do things. You just go into your mail client (probably Outlook from the sound of things) and go to the account settings, then for outging (SMTP) mail server, enter your ISP's SMTP server. It won't look any different to the recipient unless they happen to really dig into the message headers and see your ISP listed there.

Brian.

[shibili]

Delivering e-mails to the right people has already become a hassle for the normal internet marketer. Read more about this on my blog

Deliver your message to their inbox, not to junk mail…