Black lists and blocked good users - sendmail, SA and MailScanner - solved

[Götz Reinicke]

Götz Reinicke schrieb:
> Hi,
> 
> I hope, somewone can point me into the right direction.
> 
> Recently I added two blacklist-checks to our sendmail config: spamhaus
> zen and the list from the german computer magazin IX.
> 
> The good news: Spam has been about 70%-80%, now it is about 20%-30%. The
> bad news: A lot of our users have problems sendig mails from there dial
> up DSL or mobile phone network connections. I'v looked up there IPs and
> all where on the Black lists or the PBL from spamhaus. So was my Arcor
> IP last night :-)
> 
> The information from spamhaus is, to use SMTP Authentification
> (http://www.spamhaus.org/pbl/query/PBL042952).
> 
> I thought, we do use TLS and  smtp auth already, so I thought, users
> allowed to log in will be allowd to send. But I got the errormessage
> using Thunderbird 2, that our mailserver didn't support STARTTLS in
> combination with EHLO.
> 
> Outlook-users do get the message, that our server didn't support SSL,
> the server error messagt is 250.

One problem is that the mailclients report errormessages which don't
point directly to the problem. The DNSBL-Check is done bevor the
authentificationcheck.

The solution is to add FEATURE(delay_checks) to the sendmail config.

/Götz
-- 
Götz Reinicke
IT Koordinator

Tel. +49 7141 969 420
Fax  +49 7141 969 55 420
E-Mail goetz.reinicke at filmakademie.de

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