Plus nets Relay server down?

[#1]

Is anyone having problems with Plusnet's relay server for emails from a non-Plusnet ISP (relay.plus.net)?   it looks like the authorisation side of things is not working as it is constantly asking me to re-enter my password - I am coming from YOU and using Thunderbird email client.

[#2]

We can’t send emails from our other faster router, only the plusnet hub works. Something wrong or changed with email server authentication recently

[#3]

@phimmies The router you use has zero effect on your email traffic - provided it is set up correctly.

[#4]

Hi
I beg to differ. If I’m away from home using a non-plusnet connection, I had loads of problems getting the emails to send. I have had it static for many years now and it all works. But this week, from home, (using my 4G router from Three), the emails have stopped sending saying there are “errors with the password settings.” If I swap to my plusnet router, it magically works. I’ve had this setup for 3 years without issues. We are rural so can only get the 5mb copper connection from PN , the 4G was desperation during covid.

[#5]

If you are away from home, or, I SUSPECT, but don't know for sure, using the 4G router, you need to set authentication on in your email program, otherwise, the Plusnet relay will refuse connection.

[#6]

Hi guys. Thanks again. I would like to stress, this has been working for 3 years already. It isn’t one device where this has changed, it no longer working on the iPad nor the iPhone. Only the iPhone had the recent IOS update , so I’m ruling that out. I’m only trying to track down why it’s suddenly failed to authenticate. The port number hasn’t changed, nor has the outgoing server.
I’m due to go abroad for a week so want to ensure I can send emails when away from the home server. If the plusnet techies say the authentication hasn’t been changed, no upgrades to SSL (e.g. TLS 1.2 to 1.3) or any of that jazz, then I’m stumped.
I’m just trying to figure out why it’s stopped working. Sorry if it sounds harsh, it’s been a long week

[#7]

So you have set authentication to 'on'?

You say this is on iPad/iPhone - have you tried rebooting/resetting them, or deleting/re-inserting the accounts - I had this issue a long time ago. Apple kit has some funny habits.

[#8]

Hi John & co. Despite having already rebooted the 4G router, I have done a further one and the issue has “mysteriously” disappeared. Another case of turn everything on and back on …. twice !
Thanks for the support.

[#9]

@phimmies I suspect the problem was a bad reputation of the ip you had been assigned, this would cause relay.plus.net to reject the connection.Reconnecting would eventually get you a different one. Ideally the mail client ought to return the error but I'm afraid many just report an authentication error irrespective.

[#10]

My problem still exists and is not fixed: my 'old' ISP was Virgin and I seem to remember having significant problems getting that to work initially with relay.plus.net when we started the service with them. We are now parallel running with YouFibre until YouFibre 'settles' down and these glishes are sorted.

Going back to Virgin, sending via SMTP (now) works, but YouFibre still doesn't.  So it does appear to be Relay.plus.net blocking requests from YOU.

In case you are wondering, moving to YOU is FFTP,  2G up and down and 2/3 the price of Virgin: pings are a consistent 2mS.

[#11]

@madswitcher can you try the SMTP test as described here https://community.plus.net/t5/Email/No-email-this-morning-10-November/m-p/1831686#M36647 . That way we can get the exact reason for the failure

[#12]

Eventually this problem was (sort of) cured: I powered everything associated with YouFibre down and up 4 times and tested in between.  On the last one I was able to send emails. 

I assume, as one reply above suggested, that the problem was something to do with the DHCP IP address that the modem was acquiring was being blocked by Relay.plus.com for some reason.

Anyway, up and running now and thanks for the help.

[#13]

@madswitcher it was almost certainly due to your 'IP address reputation'.

From what I can determine , You Fibre use CGNAT , which means that many people 'share' the same public IP address

https://support.youfibre.com/hc/en-gb/articles/360019701017-Why-does-my-IP-address-change-

We use the Dynamic Host Configuration Protocol (DHCP) to dynamically assign IP addresses (both IPv4 and IPv6) due to the scarcity of IPv4 address caused by the rapid expansion of the internet. We also use Carrier-Grade Nat (CGNAT) for residential premises to efficiently assign our IPv4 address range.

If someone else, sharing the same public IP, has been sending spam, then the IP will acquire a poor reputation. I'm afraid the problem is very likely to reoccur, the only good thing is that the reputation tends to improve after 24h.

[#14]

Hi again MisterW

as you surmised, the situation arose again this afternoon.

So I followed you suggestion about Telnet to relay.plus.net and got the following reponse after the DOS screen goes blank

"220 avasout-peh-004 smtp relay.plus.net" - almost immediately

then after a couple of seconds

"Connection to host lost"

I also tried using port 23 which is what my SMTP server is set to in Thunderbird and got

"Connecting To relay.plus.net...Could not open connection to the host, on port 23: Connect failed"

Obviously without the quotes.  Could you kindly let me know what this means so I can pass the information onto my ISP or is the problem at the plusnet end of things?

Hope this helps to pin it down further.  Anything else I need to do?😀

Thanks again

[#15]

I also tried using port 23 which is what my SMTP server is set to in Thunderbird

It ought to be set to port 587.

Did you try telnet to port 587 ?