topic Re: tls certificate error in Email

tls certificate error

localsurfer — Thu, 02 Sep 2021 19:24:01 GMT

Hi, I've suddenly started getting TLS certifcate errors on email. (SMTP)

Nothing has changed on my account, and my wife is having the same issue with a different email address with plusnet.

Changing the port to 25 fixes the issue, but obviously only a temporary fix, but it means I know my credentials are correct.

Re-entering all my credentials doesn't fix the issue.

Server returned error: "TLS Negotiation failed, the certificate doesn't match the host., code: 0"

I can send emails through the webmail client fine, and my gmail email is working ok.

Any advice please?

Thanks

Re: tls certificate error

wakeman — Thu, 02 Sep 2021 22:21:11 GMT

@localsurfer Welcome to the forum.

Yes I have seen this all day, its stopping emails being sent via SSL (Secure encrypted email).

Its the relay.plus.net servers which have an expired security certificate.

Its needs PlusNet to fix ASAP.

Maybe if @Gandalf is around he might get this sorted 🙂

Re: tls certificate error

Gandalf — Fri, 03 Sep 2021 08:19:34 GMT

I've raised this with our email gurus and the certificate's still valid and in date our side.

Are you still having issues today?

Re: tls certificate error

mavison — Fri, 03 Sep 2021 09:25:04 GMT

I hve had similar problems yesterday evening and today with the relay.force9.net server - it claims the certificate was valid from 2/9/2020 to 2/9/2021, and so was invalid.

However, I have just tried again, and it now seems ok ... so it must have been fixed between 10:00 and 10:20 today!

Re: tls certificate error

wakeman — Fri, 03 Sep 2021 11:56:21 GMT

@Gandalf No longer getting any certificate expired messages on sending via relay.plus.net so issue seems to be fixed.

Re: tls certificate error

Gandalf — Fri, 03 Sep 2021 12:42:30 GMT

Thanks for the feedback.

I'm glad to see it's working again for everybody.

I'm not entirely sure what happened but let us know if you have issues again.

Re: tls certificate error

mavison — Thu, 09 Sep 2021 16:55:44 GMT

I now seem to be having SSL certificate problems with another email server, which seem to have started in the last few hours.

This is with the POP3 server mail.force9.net on port 995.

Details I have are:

Issued by: GeoTrust EV RSA CA 2018

Issued to: mail.plus.net (note I specified mail.force9.net)

Validity: 06 Sep 2021 to 07 Sep 2022

Error: Unverified certificate chain

Is this another Plusnet problem with email server certificates?

Re: tls certificate error

wakeman — Thu, 09 Sep 2021 17:46:32 GMT

@mavison

Yep I am seeing it as well, same error message. I do use mail.plus.net

@Gandalf Can this again be escalated to your server team. It looks like the certificates chain is incomplete and thus complaining even though its in the current date range, so should be valid.

I suppose it could just being taking a long time to propagate round your servers, but would be surprised if that was the case.

Re: tls certificate error

ChrisH — Fri, 10 Sep 2021 07:16:53 GMT

Is this fixed now? I have TLS cert issues... Started yesterday (Thurs 9th Sept) and still an issue this morning. This is getting mail with Android K9 app via POP3 (mail.plus.net / port 995). Same story on Mrs H phone, no changes made to settings in both cases.

Re: tls certificate error

adam945 — Fri, 10 Sep 2021 08:18:32 GMT

Hi @wakeman, thanks for the heads up that this still isn't fixed - I'll get an email over to the server team to let them know. Just to double check - are you able to send emails through the webmail client? I can see previously this was still possible for some. If so I'd recommend doing it that way until we get a further update from the server team and I'll keep @Gandalf in the loop for you all on this one too.

Re: tls certificate error

mavison — Fri, 10 Sep 2021 08:44:03 GMT

The SMTP cert problem was last weeks problem. Ok now.

I will not be able to check POP3 until this evening.

But I have not received any IMAP mail forsome time - no clues why.

Re: tls certificate error

ChrisH — Fri, 10 Sep 2021 08:47:35 GMT

Just checked using webmail: Yes, I can send (and receive) mail using webmail.

Re: tls certificate error

gandb1 — Fri, 10 Sep 2021 09:07:52 GMT

you must be patient! it's sooooooo slow.

Re: tls certificate error

wakeman — Fri, 10 Sep 2021 09:26:10 GMT

@adam945 @Gandalf

mail.plus.net with SSL can't connect at all now. Go through the connection motions for user name and password the no connection from the server. - connection lost

Your Service status page is still not letting people know of the issue (says its all fine when its not).

Re: tls certificate error

ChrisH — Fri, 10 Sep 2021 10:02:12 GMT

Some time in the last 5-10 mins various mails have finally arrived on my phone. They reflect what I was able to see via webmail. The W10 IMAP mail client has got the same along with my POP3 Thunderbird client.
So things are looking normal at the monent

Re: tls certificate error

mavison — Fri, 10 Sep 2021 18:57:37 GMT

Yup - my phone received many emails from IMAP this afternoon, and I have just checked the POP3 server and that also receives emails without problem.

It seems the problems have been fixed, but some comnent from Plusnet about why there have been two certificate problems with email servers in a week, and what has been done to ensure they will not happen again would be good.

Re: tls certificate error

ChrisH — Fri, 10 Sep 2021 19:23:26 GMT

Agreed! What is of concern [with the K9 mail client at least] is that you are offered the option of accepting and installing the un-authenticated cert. Mrs H pointed out the mail checking issue to me before I noticed it asking if she should just do that and carry on! Aye it might have worked, but could equally be a man-in-the-middle attempt... so this has potential security implications.
I don't know about through today, but I did not see any notification about the PlusNet eMail service having any issue (it was the first thing I looked for yesterday... after digging around for ages looking for service details) which is a bit below par for an ISP as established as PlusNet.
Anyway, I've had a busy day away but now I'm back I'm happy to see all looking as it should be this evening.

Re: tls certificate error

wakeman — Fri, 10 Sep 2021 19:29:18 GMT

Yes all seems to be working now.

@adam945 Thanks for getting this resolved, but would be interested to know why it happened in first place.