topic Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back. in Email

Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

CSG — Fri, 06 Mar 2026 17:16:49 GMT

I note that there is a separate topic regarding outgoing emails which are being rejected by Hotmail.

My situation is slightly different in that, for the some weeks, emails (previously sent successfully) to Hotmail addresses have now simply disappeared into the ether ~ they have neither been delivered nor rejected.

OK, my short term solution is to copy in family members with other email addresses, but is a solution at my end or do I simply wait for the issue to be resolved?

Thanks.

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

Peter_JW — Mon, 09 Mar 2026 11:51:36 GMT

Hi @CSG.

I've checked with this one and it is likely linked to the same issues as the other reported delivery failures.

We've fed this back, so please keep an eye out, and if you're still having trouble once the wider issues are confirmed as resolved, please let us know and we can take another look.

Peter

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

CSG — Mon, 09 Mar 2026 13:36:55 GMT

Hi @Peter_JW

Thanks for the prompt and helpful response.

Much appreciated.

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

CSG — Wed, 11 Mar 2026 17:07:17 GMT

@Peter_JW

Following my original post I have discovered why the outgoing Hotmail email ~ rejection notices have, very recently, not been reaching me!

On using Webmail to log onto my "transitioned to Greenby" account (from February 2026) I found 35 items within the Spam folder which had not been passed onto my Outlook email account ~ whether the Inbox or Spam folder !

These included the outgoing Hotmail email rejection notices, recent monthly bills from Octopus Energy and various other innocuous emails

I have turned of the Greenby Spam Filter so that I may, hopefully, see all incoming emails ~ including those designated as Spam within my Microsoft Outlook account.

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

AyToZed — Wed, 11 Mar 2026 22:02:58 GMT

I'm of the opinion it is a bit more complex than that.

Reasoning.

I have sent e-mails to a MS-type "webmail" address. They were not delivered, and neither were there NDRs.

I do not use Plusnet or Greenby e-mail.

Since there were no NDRs, the only other reason I can think of is that my e-mail provider is not entertaining NDRs, and is sending them to the bitbucket.

I have tested this scenario, and have NDRs.

(My) Bottom Line.

MS have been sending some incoming mails into their bitbucket(s). The recent news that MS are now sending out NDRs does not negate the original problem. At least an NDR is reporting a problem.

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

abitpedantic — Wed, 11 Mar 2026 22:33:10 GMT

@CSG

I presume you're using IMAP rather than POP3 for incoming mail?

Are all available email folders subscribed (many of mine became unsubscribed when I was migrated)?

Can you confirm that that doing Send/Receive All Folders in Outlook doesn't download the Junk/Spam folder?

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

JK33 — Thu, 12 Mar 2026 10:00:08 GMT

Re the Hotmail issue…I sent an email this morning to several people including three with Hotmail addresses. No problem with the others receiving it but the Hotmail have all bounced back with a “failed permanently” message. I have a Totalise email address. Can anyone help? I also had this issue with an outlook address yesterday.

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

Hortense — Thu, 12 Mar 2026 14:52:33 GMT

Me too. For the last three days emails sent to Hotmail and Outlook addresses have received the same 'undeliverable' bounce backs, whether sent individually or as part of a group mailing. This seems like a repeat of the long long saga from last year 'From address doesn't meet the authentication requirements defined for the sender' (currently up to 835 posts), which did seem to be fixed. Anyone else?

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

abitpedantic — Thu, 12 Mar 2026 15:09:04 GMT

I'm surprised that it's only been 'the last three days'. Are you actually receiving a bounce back message as in last year's thread to which you refer, or is it more like this one Hotmail rejecting mail from PN [Diagnostic-Code: s... - Plusnet Community which as you can see has been going on for the last few weeks?

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

Hortense — Thu, 12 Mar 2026 16:16:21 GMT

I've probably only tried to email such addresses fairly recently. They aren't among my most frequent correspondents. It might be longer than three days, though I suppose that was when it began to 'impinge' on me.

No, I definitely do not get those long bounceback messages about block lists, that are referred to in the thread you have highlighted. My bouncebacks are the simple "Reason: A message that you sent to the following recipient could not be delivered due to a permanent error. ** The remote server ?? responded with: ** xxxxxx@outlook.com ??:?? This message was created automatically by mail delivery software on the server ".

By the way, I see that the 'block list' thread does contain a number of posts that actually refer to my problem rather than the original one. It's become a bit confused/confusing (not a criticism, I know how hard it can be to identify a specific targeted thread to add to!)

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

abitpedantic — Thu, 12 Mar 2026 16:18:34 GMT

Are there any attachments to the bounce back message? If so, the detail is in there.

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

Hortense — Thu, 12 Mar 2026 16:47:26 GMT

Yes, there is, and I hadn't checked it. Thank you for the hint. Details.txt does contain this sentence: "Please contact your Internet service provider since part of their network is on our block list (S3150)." I don't know if that was also the case with the previous problem - I'm afraid I don't usually check such attachments. Will try to remember. Thanks again.

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

balvack2 — Sun, 22 Mar 2026 11:14:38 GMT

@CSG same issue here. No bounceback error message. We've only just found out emails sent several weeks ago have disappeared into the ether.

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

CSG — Sun, 22 Mar 2026 15:21:12 GMT

@balvack2

Since turning off the Greenby spam folder setting via Webmail, the outgoing Hotmail email rejection notices are at least ~ again ~ reaching me!

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

abitpedantic — Sun, 22 Mar 2026 16:00:51 GMT

@CSG

Since turning off the Greenby spam folder setting via Webmail, the outgoing Hotmail email rejection notices are at least ~ again ~ reaching me!

Presumably you are saying that the rejection notices now come to your Inbox but are you saying that before you turned off the Greenby spam filter the rejection notices were invisible, rather than being put in your Spam folder?

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

balvack2 — Sun, 22 Mar 2026 18:16:00 GMT

@CSG Our issue is we didn't get any 'bounceback' or non-delivery messages at all. Not in our spam folder, not in our inbox. We only know mail wasn't being received when we were talking to the intended recipient and they confirmed they hadn't received any of the emails we'd sent them 😞

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

balvack2 — Sun, 22 Mar 2026 18:51:56 GMT

We've just now discovered a workround - mail sent from webmail (name@ourplusaccount.plus.com) seems to be delivered to hotmail ok but mail from our mail client (name@ourdomain.co.uk) disappears into the ether.

At least that'll keep us going until we migrate to a new email provider ...

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

CSG — Mon, 23 Mar 2026 08:57:36 GMT

@abitpedantic

Yes ~ outgoing emails to Hotmail which had previously been bounced back to me "disappeared" following the transition to Greenby. However, after finding them isolated in the Greenby spam filter (via Webmail) and turning the Greenby spam filter off, they are again being bounced back into my email account

Doesn't ,of course, solve the main issue!

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

MisterW — Mon, 23 Mar 2026 11:23:26 GMT

@balvack2

We've just now discovered a workround - mail sent from webmail (name@ourplusaccount.plus.com) seems to be delivered to hotmail ok but mail from our mail client (name@ourdomain.co.uk) disappears into the ether.

Unless your domain has a valid SPF record and DKIM signing of your email, then email sent from it stands a good chance of being rejected, particularly by Microsoft & gmail. The anecdotal evidence that NDRs from Microsoft are being discarded by Greenby just exasperates the situation. If you're sending via the Plusnet server then you certainly wont have DKIM signing. You may have an SPF record if you've created one manually in your domain DNS but it will only be a short lived possibility. In the near future, once outgoing mail is routed via the Greenby server, it will not be possible to send from a domain address.

Re: Emails to Hotmail.com are disappearing ~ neither delivered nor bounced back.

WorldMachine — Mon, 23 Mar 2026 11:57:36 GMT

Tried several times on Sunday to send to a hotmail address and the attachment contains:

"Diagnostic-Code: smtp; 550 5.7.1 Unfortunately, messages from [212.159.14.18] weren't sent. Please contact your Internet service provider since part of their network is on our block list (S3140). You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors. [Name=Protocol Filter Agent][AGT=PFA][MxId=11BD0A0C2BBF1E23] [DB1PEPF00039234.eurprd03.prod.outlook.com 2026-03-22T10:05:54.897Z 08DE85061A8D19FD]

Last-attempt-Date: Sun, 22 Mar 2026 10:05:54 +0000

Given that this has been ongoing for several weeks with customers providing plenty of information within reports, please can Plusnet provide an update. It really should not be taking this long to fix, I believe the move to Greenby was promised to be a "seamless experience."