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TedMoreyFlag for United Kingdom of Great Britain and Northern Ireland

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New server SMTP delivery setup

Hi - I'm setting up a new IIS6 server on Windows 2003 and want to use the SMTP virtual server to deliver email from the website hosted on the server. I have restricted relaying to just 127.0.0.1 - i.e. only the local machine can relay emails. Do I need to do anything else to stop the server being abused for spam relay??

When I attempt to send email from the website contact form (ASP) I can them getting stuck in the mailqueue folder and errors messages are being generated saying that messages cannot be delivered. I have enabled logging for the SMTP service and can see the following line displayed...

550+Access+denied+-+Invalid+HELO+name+(See+RFC2821+4.1.1.1)

This is where the water gets a bit murky for me - I have looked at a few posts on here and they start talking about PTR records - which I don't understand. Please can someone talk me through what needs to be setup to overcome this problem.

Thanks
Ed

PS - in the SMTP log I can also see the following entry re-occurring every 15 minutes or so...

554+RBL+rejection:+http://www.spamhaus.org/SBL/sbl.lasso?query=SBL100841

Is this a good or a bad thing??







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kloux
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Hi - we are taking over the running of the website from another company and currently the www address is pointing somewhere else. Once everything's ready we'll repoint the DNS to this new machine.

So what reverse DNS entry do we need to setup - i.e. which domain should it point to - ours, our client's or the ISPs??

Thanks
Ed
Let's say you just need an app to send out mail.  You could setup a record for app.domain.com.  Point the reverse that that IP.
Hi - I asked my ISP setup a PTR record for the IP address and it turns out that there already was one. I therefore retried to resend from the website forms and this time in the logs a different error was reported stating that the mail could not be delivered because the originating IP address is on a zen.spamhaus.org blacklist. This is odd because we have only just set this server up - upon closer inspection on the spamhaus site i think it is because someone with a similar IP address has previously done something naughty and we have been tarred with the same brush. I am now going to embrak upon contacting spamhaus - but in the short term I'm going to use authsmtp.com as a relay server to deliver emails from this server for me (using the IIS6 smarthost feature).