Unable to connect to imap email servers

[#1]

@Artron That would make no difference - it is a mail server issue.

[#2]

@jab1 The diagnostic instructions Townman linked to have this example:

535 ...authentication rejected as source IP has a poor reputation

I didn't think it was very likely to sort the problem, but it seemed worth a quick try.

[#3]

@Artron thanks. Are you at home, using your PN connection? If so, that response looks suspect to me.

[#4]

@Artron 

Thats a helpful diagnostic.  Would I be correct that you are not a Plusnet ISP connection?

You have a compromised IP address.  Nothing wrong with the Plusnet service.  You are not going to get anywhere until you acquire a clean IP address.

All of that said, this thread is about connection to the IMAP server failing.  Your issue is with the SMTP server - that is something entirely different.

[#5]

@jab1 Yes, I'm at home on my PlusNet connection.

But you're right - I was blindly pasting in the "callnetuk.com" variants of the cURL commands. If I switch to a different browser, it copies the correct commands to my clipboard and tells me that it's done so. So let's try those 😀

Using this command

$ curl -v pop3s://mail.plus.net -u ...

I now get a minute of inactivity followed by:

* server response timeout
* Closing connection 0
* TLSv1.2 (OUT), TLS header, Unknown (21):
* TLSv1.2 (OUT), TLS alert, close notify (256):
curl: (28) server response timeout

The SMTP variant

$ curl -v smtp://relay.plus.net:587 -u ... --ssl-reqd

now goes straight in, prints its help message about contacting the postmaster, then says:

214 end of HELP info
* Connection #0 to host relay.plus.net left intact

The IMAP variant gets to the LOGIN command, then pauses for about 30 seconds, then says:

* TLSv1.2 (OUT), TLS header, Unknown (21):
* TLSv1.2 (OUT), TLS alert, decode error (562):
* OpenSSL SSL_read: error:0A000126:SSL routines::unexpected eof while reading, errno 0
* Closing connection 0
curl: (56) OpenSSL SSL_read: error:0A000126:SSL routines::unexpected eof while reading, errno 0

Perhaps that means my cURL is out of date, but I installed it only half an hour ago.

[#6]

I’ll try to take a look.

[#7]

I don't think an IP address has anything to do with my problem. I've tried a vpn and mobile data service. Same result as usung home IP.

[#8]

Probably of no use, but a test to and from one of my .icloud addresses passed without issue. I'm not with PN, and using authentication.

[#9]

We can definitely rule out the IP address. I've rebooted my router 3 times in the last 60 minutes, and have been unable to log into webmail or connect with IMAP or POP3 from any of those 4 dynamic addresses.

[#10]

Need to look at what is known and work out what the difference are from there.

On Windows 11 testing to a Plusnet DEFAULT mailbox and a SECONDARY mailbox IMAP, POP3 and SMTP connections are all successful.

Therefore we need to look at the issues being elsewhere.

Someone reported a 535 bad IP error - that is a SMTP connection error from a dirty IP address - remedy for that is find out your current IP address, disconnect form the internet for two hours, reconnect and check to see that you have a different IP address and try again.

Someone reported using curl -v along with TLS issues (not curl.exe -v) so I conclude that is not a windows environment and possibly does not have a clean TLS configuration.  Please re-run the test droping the "d" from pop3s and imaps and drop the --ssl parameter off the SMTP test.

Can everyone else please do full diagnostics - need more details than have been shared, notably the target service IP addresses.  The only things you need to redact are your credentials and the long string of garbage ... which is the encryption of your credentials.

For the avoidance of doubt, for a *.plus.com account I cannot detect issues from here, so in principle the services are fully functional.

EDIT: I have a static IP address and therefore am on a different network... I will retest OFF network

[#11]

I also had the same issues whether logging on from my PC which is connected through Plusnet Broadband service (either native or using VPN) and also using a mobile phone which is connected via the EE network. 

Just this second it started working again!

[#12]

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@Artron wrote:

We can definitely rule out the IP address. I've rebooted my router 3 times in the last 60 minutes, and have been unable to log into webmail or connect with IMAP or POP3 from any of those 4 dynamic addresses.

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Unless you have expressly verified that the IP address changed, this is no assurance.  Plusnet dynamic IP addresses are very sticky; what you describe has a very high possibility of returning the same IP address.  A disconnection of 90+ minutes is usually required to give a reasonable level of confidence to obtain a different IP address.

[#13]

@Townman 

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Someone reported a 535 bad IP error - that is a SMTP connection error from a dirty IP address

That was me, but I wasn't reporting it: I was just pointing to it (it's an example in the diagnostic instructions) as the reason why I tried rebooting my router. Apologies for the confusion.

But...

As of a couple of minutes ago, the problem has vanished. I can now access my email account through my email client and through webmail.

[#14]

@Townman I checked my IP address after rebooting the router, and it was different each time.

[#15]

No problem found connecting from off network.

I doubt that there are any support staff around ... but I will ask!

@Artron - glad that you appear to be sorted.