Geekzone: technology news, blogs, forums
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.


273 posts

Ultimate Geek

# 142417 12-Mar-2014 14:05
Send private message

Hi guys,

A school I support is a CallPlus UFB customer with outgoing mail routed through

Lately we've been having some mail bounce with messages coming back to us such as:

<<< 554 5.7.1 <(redacted)@(redacted)>: Recipient address rejected: [RBL_007] your ip is listed on RBL and does not match
554 5.0.0 Service unavailable
<<< 554 5.5.1 Error: no valid recipients

Other bounce messages (from the Ministry of Education specifically) say "unknown recipient" for people in mid-conversation - usually messages before and since to/from the same recipient go through. I suspect the MoE server is really rejecting because of RBL matches too.

Sure enough, plugging ( into's Multi-RBL scanner has it come up on SORBS, and plugging "" into SORBS' database check comes up with this:

CallPlus SORBS listing screenshot

I've had this back from a member of the CallPlus business helpdesk:

It seems like the sender’s server check is having an error which causes the email to bounce back. We have checked on our end and it seems like the configuration is up to specification. The spam report from SORBS did not cause this problem as well.

Can some mail gurus provide their opinion as to what is going on here?



edit: typo in subject line "bounce" -> "bounces"

Create new topic


273 posts

Ultimate Geek

  # 1004315 12-Mar-2014 14:56
Send private message

Ah. I've since been pointed (edit: thanks @nzsd) to SORBS' reputation as being overzealous and a bit of an extortion house (you sometimes have to pay to be removed from their blocklist).

Create new topic

Twitter and LinkedIn »

Follow us to receive Twitter updates when new discussions are posted in our forums:

Follow us to receive Twitter updates when news items and blogs are posted in our frontpage:

Follow us to receive Twitter updates when tech item prices are listed in our price comparison site:

News »

Intel expands 10th Gen Intel Core Mobile processor family
Posted 23-Aug-2019 10:22

Digital innovation drives new investment provider
Posted 23-Aug-2019 08:29

Catalyst Cloud becomes a Kubernetes Certified Service Provider (KCSP)
Posted 23-Aug-2019 08:21

New AI legaltech product launched in New Zealand
Posted 21-Aug-2019 17:01

Yubico launches first Lightning-compatible security key, the YubiKey 5Ci
Posted 21-Aug-2019 16:46

Disney+ streaming service confirmed launch in New Zealand
Posted 20-Aug-2019 09:29

Industry plan could create a billion dollar interactive games sector
Posted 19-Aug-2019 20:41

Personal cyber insurance a New Zealand first
Posted 19-Aug-2019 20:26

University of Waikato launches space for esports
Posted 19-Aug-2019 20:20

D-Link ANZ expands mydlink ecosystem with new mydlink Mini Wi-Fi Smart Plug
Posted 19-Aug-2019 20:14

Kiwi workers still falling victim to old cyber tricks
Posted 12-Aug-2019 20:47

Lightning Lab GovTech launches 2019 programme
Posted 12-Aug-2019 20:41

Epson launches portable laser projector
Posted 12-Aug-2019 20:27

Huawei launches new distributed HarmonyOS
Posted 12-Aug-2019 20:20

Lenovo introduces single-socket servers for edge and data-intensive workloads
Posted 9-Aug-2019 21:26

Geekzone Live »

Try automatic live updates from Geekzone directly in your browser, without refreshing the page, with Geekzone Live now.

Support Geekzone »

Our community of supporters help make Geekzone possible. Click the button below to join them.

Support Geezone on PressPatron

Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly to your computer or smartphone by using a feed reader.

Alternatively, you can receive a daily email with Geekzone updates.