[deb8] Email bounces for some recipients with error: status 5.0.0

[JAYDUDY]

I have installed a clean Debian Jessie on a VPS with dedicated IP and SSL in place. And the latest version of DA ofcourse+CSF+Spamblocker exim.conf.

When I send email to some recipients (e.g. [anybody]@connect4you.nl) then I get an immediate response/bounce:
"Reporting-MTA: dns; mail.kaputo.com
Action: failed
Final-Recipient: rfc822;[person]@connect4you.nl
Status: 5.0.0"

I discovered a week ago that the mail server-address (not the domain's IP) was on a blacklist at Spamhaus.
I removed the (apparently) vulnerable Wordpress Contact Form7-plugin from the bouncing domain and had the server IP removed from the blacklist successfully.
But... still no luck. Email keeps bouncing for some specific recipients.
The error isn't clear on it's root cause. Is this even related to the earlier spamflag or is it a misconfiguration in Exim? Or is the server blocking itself somehow due to RBL's being used by Exim?

I am clueless, if anyone has any suggestions please let me know. TNX

 

[SeLLeRoNe]

Is your server hostname mail.kaputo.com?

You receive this error when you receive an email or when you send?
Are you having problems with other provider (ex. gmail)?

Regards

 

[JAYDUDY]

Is your server hostname mail.kaputo.com?

You receive this error when you receive an email or when you send?
Are you having problems with other provider (ex. gmail)?

Regards

TNX
I receive the error in a bounce-mail after I send an email, bounce-mail header:

Return-path: <>
Envelope-to: [email protected]
Delivery-date: Wed, 31 Aug 2016 23:15:15 +0200
Received: from mail by mail.kaputo.com with local (Exim 4.87)
id 1bfCqp-0005GP-Ud
for [email protected]; Wed, 31 Aug 2016 23:15:15 +0200
X-Failed-Recipients: [email protected]
Auto-Submitted: auto-replied
From: Mail Delivery System <[email protected]>
To: [email protected]
Content-Type: multipart/report; report-type=delivery-status; boundary=1472678115-eximdsn-1638650703
MIME-Version: 1.0
Subject: Mail delivery failed: returning message to sender
Message-Id: <[email protected]>
Date: Wed, 31 Aug 2016 23:15:15 +0200


The original hostname was the server's address: vps837.directvps.nl (the address that was marked for sending spam in the past), I changed it in Exim.conf to a domain specific hostname, mail.kaputo.com, to check if that would bypass any spam flags and allow mail to be send to these bouncing recipients.
There was no effect from the change in hostname when sending mail; I get the same immediate error response. Could it be that Google not only marks the hostname (send by address) but also all related From (domain specific) addresses?
I tried as many blacklist checkers I could find: both hostname (IP) as domain address (IP) are OK. I can speculate some mailservers hold a long retention period or don't care about blacklist removal.

One of the bouncing recipients uses Google Apps (mail hosted by google), but sending mail to a regular (free) gmail-account doesn't bounce.
Another bouncing address is hosted at Strato (a different VPS hoster from mine), not related to Google.

Because the bounce error is so vague I am not convinced it's due to the earlier spam flag issue.

Personal problem is that I can't handover the VPS to a customer if outgoing mail is bouncing like this.

 

[ikkeben]

Don't know if also spf record info could be a spam blocking for the old hostname ? >

v=spf1 a mx:mail.kaputo.com ip4:127.0.0.1 ip4:194.145.200.170/24 a:ns0.transip.net a:ns1.transip.nl a:ns2.transip.eu -all include:vps837.directvps.nl

And reverse lookups.