From address doesn't meet the authentication requirements defined for the sender

[#1]

SPF is already set at sub-domain level, and in combination with the protocols set at parent domain level should be sufficient.

[#2]

Thanks @jab1 , maybe I should have made that clear in my post.

[#3]

Thanks - so it seems that Plusnet has configured it's servers correctly. Therefore, is it solely a case of Microsoft configuring something correctly at their end?

[#4]

Expecting Microsoft to back out a change that was intentionally made to curtail spam is wishful thinking.

Typically changes of requirements by the likes of Microsoft or Oracle or Amazon do not go away.

[#5]

My expectation is not for Microsoft to "back out the change", it is for them to correctly configure their settings to accord with e-mail providers like Plusnet who use a sub-domain approach for e-mail addresses.

Why is this a problem, given from what we've read earlier in this thread, Plusnet is not alone in having these problems.

[#6]

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@ebforum wrote:

Why is this a problem, given from what we've read earlier in this thread, Plusnet is not alone in having these problems.

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This 'reducing spam' claim is very questionable, IMO, especially when the other big player in this fiasco, with similar claims for their action - Gmail - allow their Googlegroups to actively post spam. 

[#7]

It therefore begs the question......

Is there a way forward for Plusnet e-mails?

I'd prefer an honest answer directly from Plusnet so that those of us who are impacted can think about making other arrangements. However, to change e-mail provider is going to be a very significant issue for Plusnet's users.

[#8]

@ebforum Unless things have ground to a halt - which I doubt - there is still work being done to resolve this issue, but I can understand why it may appear not be the case. A lot of inter-company discussion is not reported to customers, for various reasons.

[#9]

It would really help if James_B can provide further information given the date of the last update in the service information is as below. I'd like to be informed specifically on:

1 is Plusnet's e-mail service configured correctly?

2 if 1 is correct, does Microsoft accept that the problem resides in their e-mail service?

3 if 2 is correct, when does Microsoft intend on implementing a working solution?

4 if 2 is not accepted by Microsoft, what is the way forward.

Update 15/07/2025

We're aware that some customers are still seeing delivery failures when sending emails to multiple recipients with Microsoft-owned domains. As the original issue has been resolved, a new support ticket has been opened to investigate this specific problem. 

[#10]

1) .As there don't appear to be issues sending to other email platforms other than MS ones, I would suggest the answer is yes.

2) and 3) Ask Microsoft.

4) Who knows - what would you suggest?

[#11]

5 What could be done to the Plusnet email platform to prevent our emails appearing to be one sender i.e. more like most other ISPs / mail providers ?


These are not criticisms.

We are all wishing to avoid the pain that comes with being forced into a change of email provider,
and I mean to a 123Reg domain etc not to Greenby.  

[#12]

@jab1 in answer to your response below:

2) and 3) Ask Microsoft.

4) Who knows - what would you suggest?

I expect the service provider, Plusnet, to advise on 2 and 3. I am not a technician so your answer to 4 is not helpful and once again flippant in consideration of the problems Plusnet e-mail customers are facing. I expect Plusnet and Microsoft to jointly agree the way forward and let its customers know.

[#13]

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@Townman wrote:

Microsoft have not offered any answers...

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For your, and @MisterW's, information, my experience today is different to what I've seen before.

I sent a message from my [name]@[accountName].plus.com address, using Win10 Pro/Outlook 2016/POP3, TO one address @live.com and one address @outlook.com.

The message to the @live.com address (which was the first one I'd entered into the TO field) bounced almost instantly but the one to the @outlook.com address did not produce a bounce.

That's progress of sorts since previously when I sent to both of these addresses at the same time both messages would bounce.

The reason for the failure of the one that bounced was as before (Spf= Pass , Dkim= Fail , DMARC= Pass).

[#14]

I have just sent one e-mail with my test Outlook.com account and my wife's Gmail account in the To field.

Outlook.com bounced it back with Dkim= Fail. Gmail accepted it.

This is the same as a week ago.

[#15]

I don't know if this is relevant, but I have a mailing list with two hotmails and an msn address, and the whole list is blind copied and sent using linux/kmail. Fairly early in this whole discussion all three bounced, but I think it has been OK since. More recently I asked one of the hotmail recipients about my last 3 messages, and he had received them. He had me on his safe senders list because of earlier problems, and he said they came with a pink banner saying "The digital signature on this message can't be verified. This message has a digital signature, but it wasn't verified because the S/MIME extension isn't installed. Please contact your IT administrator for help installing the extension."