topic Re: Plusnet emails - 550 Bounce messages. in Email

Plusnet emails - 550 Bounce messages.

AlbertHerring — Fri, 29 Aug 2025 14:35:50 GMT

Now in the same boat. Mails on domain, mostly from Thunderbird, outgoing messages from relay.plus.net getting a 550 bounce message (domain "blacklisted by local policy"). Has started this morning, was working fine previously (but was away last weekend so no idea if it was happening then as well).

Phone support seems to have gone into a loop running unnecessary connection tests (connection is working just fine). Yay for boring dystopias.

Re: Plusnet emails refusing to send.

jab1 — Fri, 29 Aug 2025 10:33:03 GMT

@AlbertHerring Are these emails to Microsoft hosted addresses (Hotmail/Live etc.)?

Re: Plusnet emails refusing to send.

AlbertHerring — Fri, 29 Aug 2025 10:37:06 GMT

@jab1 Not MS domains. The bounce messages are from PN (relay.plus.net) itself.

Re: Plusnet emails refusing to send.

jab1 — Fri, 29 Aug 2025 10:40:21 GMT

@AlbertHerring Do you still have the bounce messages? If so, can you post them, in full, redacting the recipients identity?

Re: Plusnet emails refusing to send.

AlbertHerring — Fri, 29 Aug 2025 10:54:45 GMT

@jab1 Slight correction - the bounce message is from my own local relay, reporting the bounce from relay.plus.net

This is the mail system at host [my local server].

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                   The mail system

<xxxxx@xxxxx.com>: host relay.plus.net[212.159.9.107] said: 550
    <xxxxx@hugh.es> sender domain rejected (blacklisted by local policy) (in
    reply to MAIL FROM command)

Reporting-MTA: dns; [my local server]
X-Postfix-Queue-ID: 020ED1B825F7
X-Postfix-Sender: rfc822; xxxxx@hugh.es
Arrival-Date: Fri, 29 Aug 2025 10:39:37 +0100 (BST)

Final-Recipient: rfc822; xxxxx@xxxxx.com
Action: failed
Status: 5.0.0
Remote-MTA: dns; relay.plus.net
Diagnostic-Code: smtp; 550 <xxxxx@hugh.es> sender domain rejected (blacklisted
    by local policy)

which looks to me like very much the same issue other users on this thread had last weekend (when I was in a blissfully disconnected campsite somewhere, so no idea if it would have affected us then).

Re: Plusnet emails refusing to send.

jab1 — Fri, 29 Aug 2025 10:55:27 GMT

@AlbertHerring Is the 'hugh.es domain yours (hosted by another entity other than Plusnet)? If so, I'm guessing that trying to use the PN relay for it is the cause of your issue.

Maybe @MisterW or @Townman could confirm/deny my suspicions. (I'm no expert).

Re: Plusnet emails refusing to send.

Townman — Fri, 29 Aug 2025 10:59:03 GMT

@AlbertHerring

This is not the same issue, I have asked the mods to split off your posts into your own topic, after which we can give you focussed responses and not confuse @Sick_of_PN 's thread.

Re: Plusnet emails refusing to send.

AlbertHerring — Fri, 29 Aug 2025 11:03:59 GMT

@Townman OK, thanks, will hold fire for the moment.

Re: Plusnet emails refusing to send.

Baldrick1 — Fri, 29 Aug 2025 16:22:34 GMT

Moderator's note:
Thread moved to it's own topic. https://community.plus.net/t5/Email/Plusnet-emails-550-Bounce-messages/m-p/2018621#M52266

Re: Plusnet emails refusing to send.

MisterW — Fri, 29 Aug 2025 14:56:31 GMT

@AlbertHerring it looks like you are running your own mail server for the hugh.es domain. The MX record is pointing to what appears to be a Plusnet static IP. The domain is not hosted by Plusnet and has no SPF record.

Its not surprising therefore that mail sent from hugh.es is being rejected. At a minimum you should set your mail server to send using relay.plus.net as a smart host and add an appropriate SPF record to your domain DNS

Re: Plusnet emails refusing to send.

AlbertHerring — Fri, 29 Aug 2025 15:05:59 GMT

@MisterW I am indeed (I accept that running my own mail servers was a very bad life choice, but not one I want to unravel right now, as it's been working for a couple of decades until this morning, the last few years on here). Will update the DNS and see if that sorts it.

Re: Plusnet emails refusing to send.

AlbertHerring — Fri, 29 Aug 2025 15:34:38 GMT

@MisterW Added SPF records including the servers mentioned in https://community.plus.net/t5/Email/SPF-record-2022-update-please/td-p/1882388 for the domain, plus relay.plus.net - no immediate joy but I assume I will need to allow the changes to propagate before I can tell whether I've done it correctly.

Re: Plusnet emails refusing to send.

MisterW — Fri, 29 Aug 2025 15:34:49 GMT

@AlbertHerring I'm afraid the email world is changing, now you need at least SPF and/or DKIM and preferably DMARC to reilably send from your own domain.

Try setting an SPF of v=spf1 +a +mx include:_spf-internal.plus.net include:_spf-internal2.plus.net that should cover both your own server (the mx) and Plusnets relays. If sending from your own server still deosnt work, quite likely as your IP may well be on the PBL , then as I said earlier you need to set your server to smart host via relay.plus.net

Re: Plusnet emails - 550 Bounce messages.

MadDogPikey — Wed, 03 Sep 2025 09:59:49 GMT

Hi Guys,

I'm also suffering this problem with domain emails not sending for the last 6 weeks (although working for the last 10+ years) but also through webmail with the following error:

SMTP Error (550): Failed to set sender

"xxx.xxx@pinaret.co.uk" (<xxx.xxx@pinaret.co.uk>

sender domain rejected (blacklisted by local policy)).

The domain is (currently) hosted by Plusnet, but they've been completely unable to resolve the issue for the last month and don't really appear to have a clue how to fix it either, so hoping some real experts might be able to help here?

Let me know if there's any more detailed technical info I need to provide to assist.

Cheers and fingers crossed

Malcolm

Re: Plusnet emails - 550 Bounce messages.

Townman — Wed, 03 Sep 2025 12:32:30 GMT

@MadDogPikey

Hi Malcom,

A warm welcome to the forums. This does look odd!

Your domain is hosted in the Force9 space and there is the correct SPF configuration on the domain, so nothing to do there.

Is this the default mailbox or a secondary mailbox you are sending from?

Are you running your own mail service or are you sending from an email client direct to relay.force9.net?

How are you logging on to the server - account name, force9 email address, or an email address on your domain?

The other possibility is that there has been suspicious activity associated with the account and it has been black-balled. @plusnettony - is that something in your space you can explore please?

Re: Plusnet emails - 550 Bounce messages.

MadDogPikey — Wed, 03 Sep 2025 12:56:17 GMT

Hi @Townman ,

Thanks for the prompt response.

It's failing on all of the email addresses that use the pinaret.co.uk domain naming, but works OK from the the 'hidden' force9 email addresses. Receiving emails is fine on all fronts.

I either use Microsoft Outlook or Plusnet webmail to access my emails and it's failing in both (as well as the mail apps on my phone), but the error message I posted was directly from webmail. If I recall, the symptoms in Outlook are the plusnet login dialogue for the email account pops up and says invalid password (even though it isn't), but I can't check this as I'm away from my home PC with Outlook on it.

I'm logging onto the webmail server with account_name+email_user_name and the password and the force9 company, which is what I've done for years without any issues.

It's possible that there may have been some suspicious activity on the account, as I started to get a few bounce errors for undelivered emails (that I hadn't sent), but I changed the password on the affected account and these stopped. Plusnet support said they'd checked all of the black lists and the domain name wasn't there, so that was a dead end.

Really appreciate your assistance, as I've been feeling pretty helpless these last few weeks and haven't seen any sign of a solution.

Malcolm

Re: Plusnet emails - 550 Bounce messages.

Townman — Wed, 03 Sep 2025 13:21:32 GMT

@MadDogPikey wrote:

I'm logging onto the webmail server with account_name+email_user_name and the password and the force9 company, which is what I've done for years without any issues.

So you log in to a secondary mail box using webmail and the account name variant of the credentials. That eliminates...

Logon using email address credentials issues (something I need to revisit)
SMTP logon from a black listed IP address
SMTP logon from an off network IP address

However if you send using an identity of @yourdomain.co.uk you get an IMMEDIATE error within the webmail client irrespective of the addressee and there is no attempt to send the email. If you use an identity of @account.forece9.co.uk the email sends fine?

@plusnettony - can NetOps be engaged please?

Re: Plusnet emails - 550 Bounce messages.

plusnettony — Wed, 03 Sep 2025 13:30:37 GMT

I've asked the question, and I'm trying to replicate with my domains,.

Re: Plusnet emails - 550 Bounce messages.

MadDogPikey — Wed, 03 Sep 2025 13:35:57 GMT

@Townman ,

That is a perfect summary of the issue, so hopefully @plusnettony or NetOps can get involved and find a solution?

Thanks,

Malcolm

Re: Plusnet emails - 550 Bounce messages.

Townman — Wed, 03 Sep 2025 14:10:04 GMT

@MadDogPikey

Hi Malcolm,

I have been kicking some tyres and I now have a key question:

In respect of the email address / identity used as email-address@yourdomain.co.uk is email-address a real mailbox or is it an email address which would be caught by the catchall if sent to?