topic Re: Mail Delivery Failed in Email

Mail Delivery Failed

WearingPurple — Thu, 05 Feb 2026 23:18:11 GMT

Please can someone help on why over the past few days I get a bounce back saying 'Mail Delivery Failed. This is a Permanent Error' type message. It's happened when sending to different email addresses and yes, I do have the correct addresses! I am connected to the internet. It's really frustrating!

Re: Mail Delivery Failed

abitpedantic — Fri, 06 Feb 2026 11:11:44 GMT

If there is an attachment to the failure email that you can open, you may find that your problem is covered in this thread Hotmail rejecting mail from PN [Diagnostic-Code: s... - Plusnet Community.

As yet there is no solution although, as you will read (message #35), Plusnet are working on getting the servers removed from other providers' block lists.

Re: Mail Delivery Failed

KarenB2 — Fri, 06 Feb 2026 17:23:03 GMT

How do I find message #35 ?

Re: Mail Delivery Failed

jab1 — Fri, 06 Feb 2026 17:35:04 GMT

@KarenB2 Click the linked topic (in pink) and scroll through to the message.

Re: Mail Delivery Failed

JaAm — Sat, 07 Feb 2026 04:08:25 GMT

Hi,

I was migrated to Greenby last week and its been a very difficult week.

Firstly it wouldn't log me on, then after a very long drawn out chat - 3 hours in total - after various config tweaks, it started to work. However when I checked one of my other ex Plusnet mailboxes, it was working on the original settings - pop3 and smtp port numbers 110 and 25. So I changed my main mailbox back to these settings and it is working. albeit with some intermittent login problems.

In can accept these as teething problems.

However my main problem now is despite being able to email a BTInternet.com a/c earlier in the day, I am now getting bounced with "554 message rejected" to the same BTInternet.com address.

We now seem to be back with the long term Plusnet problem of being blacklisted or not having the correct authentication credentials - forgive my ignorance with the terms used but I am hoping you know what I mean.

Plusnet eventually resolved this issue, although not completely but at least the service was in the main usable.

I realise this is a Greenby issue but as Plusnet have recently been dealing with much the same problem, perhaps they could liaise with Greenby to get this sorted ASAP.

In addition I am currently unable to logon to Greenby to log this fault.

Perhaps the the extremely knowledgeable superusers could also get involved - are you listening Townman?

Lets hope this issue can be resolved quickly.