No email since 14:00 yesterday

[#1]

No incoming email since yesterday afternoon. Tested today with three devices, nothing received.

Outgoing email ok.

What's up, PN?

Edit: some emails now being received, others aren't.

Edit2: other emails (tests from gmail) now also arriving.

PN, pls ignore for now.

[#2]

Resurrected.

Exactly the same thing today: no email since 14:02.

[#3]

Too much of a coincidence for exactly the same thing to happen on consecutive days.

Outgoing mail works. No incoming: tried on two devices just now.

[#4]

It improved but now I can't send email due to a PN server problem.

[#5]

Hiya @Mardler, I'm sorry for the issues with your mail. 

Are you receiving mail OK if using webmail.plus.net?

[#6]

Thanks for your response, Lauren.

Yes, incoming email is fine at least for now.

I remain unable to send email. Two errors: as yesterday and now "the username or password for relay.plus.net is incorrect". I have changed nothing. I have had this error before, neither I nor PN could correct it but eventually the server fault resolved itself.

I do not use webmail directly, I use the iOS mail app.

I suspect that it's a PN mail server fault again.

[#7]

Hi Lauren,

I just sent an email successfully using webmail.

It's the relay server that's the problem.

[#8]

Thanks for letting me know. 

Are you using a Plusnet connection when trying to send mail from your client? What are your settings? What specific error are you seeing?

[#9]

Which email brand?

There are two concurrent threads on issues with accessing the SMTP servers - see https://community.plus.net/t5/Email/SMTP-gateway-issue/td-p/1890089/jump-to/first-unread-message

Also, this diagnostic might be informative.

Test SMTP authentication

Email programs often report username / password error for issues not actually related to those being wrong, but for other connectivity issues. Such can be very frustrating when you are convinced that they are correct. Testing SMTP authentication through a command line interface can deliver a more precise error message. The following describes how to do this using TELNET.

This is not difficult, but you need the following resources which might be unfamiliar...

1. TELNET - this might need installing as an additional option, for Windows see enabling TELNET.
2. A code64 encoder / decoder such as this.

You can use TELNET to communicate direct with the SMTP server as follows...

Open the code64 encoder in a web browser and leave ready for use in the following steps.

Launch a windows command line window (DOS window) - press windows-key+R - type CMD into the run box - click OK

Enter...

telnet relay.plus.net 587

Press enter. Note if you use one of the other brand email services, use the appropriate SMTP server name for that brand. In response to SMTP server I'm here message, say 'HELLO'...

EHLO relay.plus.net

The SMTP server will then report what it can do after which tell the server you wish to authenticate...

AUTH login

The server should return the following, which is a base64 encoded string that requires your username:

334 VXNlcm5hbWU6

Use the code64 encoder to encode your username and paste it into the telnet window and press enter. For example:

bXl1c2VybmFtZQ==

The server should return the following, which is a base64 encoded string that requires your password:

334 UGFzc3dvcmQ6

Paste the base64 encoded password for the username. For example:

bXlwYXNzd29yZA==

The server will then report success or failure, any failure message should clearly indicate the reason for the failure. If the reason for the failure is not clear, please report back the message.

Close the SMTP / TELNET session by entering

quit

The session should look something similar to the below wherein your input is in bold...

220 avasout03 smtp relay.plus.net
EHLO relay.plus.net
250-avasout03 hello [your IP address], pleased to meet you
250-HELP
250-AUTH LOGIN PLAIN
250-SIZE 104857600
250-PIPELINING
250-8BITMIME
250-STARTTLS
250 OK
AUTH LOGIN
334 VXNlcm5hbWU6
bXl1c2VybmFtZQ==
334 UGFzc3dvcmQ6
bXlwYXNzd29yZA==
235 ... authentication succeeded
quit
221 avasout03 smtp closing connection
Connection to host lost.

Here are some examples of failure responses...

535 ...authentication rejected [as username / password is wrong]
535 ...authentication rejected as source IP has a poor reputation
535 Too many SMTP auth failures. Please try again later.

[#10]

Hi Lauren,

The setting are completely unchanged.

The error messages specifically gave a PN outgoing mail server fault which has happened before.

However today my test emails are being sent and received.

Except one, the one that started the problem. This still cannot be sent. This time the problem is reported as failure to send the message content to the server. The fault has been pinpointed but not the reason:-

The email included a link to a newspaper's review of two local hostelries. It simply will not send. So I figured that if my test emails are ok but don't have this email url (in fact none) stripping out the link might work: it did! Using just the url also fails.

I will try sending a different url and see what happens.

[#11]

I just tried sending an email with a different url (this page) and it failed with the incorrect username or password error message: the settings are correct and have never been changed.

I then tried an email with plain text, it also failed with that error.

This is a fault I have experienced several times over the last few years. It has always been a PN server error never at this end.

Once again I am unable to send emails.

What is intriguing this time is that the fault with the "rogue" url seems to trigger a pattern of closure, it's almost as though some monitoring algorithm has been tripped.

PS: I have no intention of posting my email settings here but please be clear that they have not been changed and have been checked.

[#12]

Update: the two plain text emails in my outbox were just sent and received! The one with the url of this page also went and was received. I did nothing except watch them go.

The two with the newspaper url have not been sent.

A fresh test email was sent and received instantly.

What is going on?

[#13]

What is intriguing this time is that the fault with the "rogue" url seems to trigger a pattern of closure, it's almost as though some monitoring algorithm has been tripped.

It is!. The content of the email is being seen as spam. The server is reporting an error BUT your email client is not reporting it accurately, many don't!. The client simply detects that the email hasnt been sent, but doesnt process the actual error code (probably 552 in this case) and just reports that it was likely an authentication error, which it isnt.

[#14]

Thanks, MisterW, that's exactly what I was thinking.

If PN come back I will post the offending url here.

ITM, plain text emails are going and no doubt other urls too though I haven't bothered trying.

PN???