Menu
Reply
WelshGasman
  • 38
  • 0
  • 4
On our wavelength
467 Views
Message 1 of 17
Flag for a moderator

Telnet into pop server?

Hi all,

Is it still possible to telnet into mail servers?
I tried but although it looks like I got in, I do not get any prompts for user or pw?

My POP email on ntlworld.com packed up today and NTL were unable to help as I use Outlook?

I keep getting asked for the username/password. Same for Virginmedia address.

Nothing changed at my end for years?

Found a workaround for the moment, but curious as to whether telnet has now been blocked on servers for security reasons?

Tags (1)
0 Kudos
Reply
Graham_A
  • 16.54K
  • 2.32K
  • 7.07K
Very Insightful Person
Very Insightful Person
455 Views
Message 2 of 17
Flag for a moderator

Re: Telnet into pop server?

@WelshGasman As you have found out per your other post the answer is to remove the 'recent''.

This has actually been redundant since 2015 when Google apps for ISPs was closed down.

________________________________
Graham

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media, I'm a VM customer. There are no guarantees that my advice will work. Learn more

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks

0 Kudos
Reply
WelshGasman
  • 38
  • 0
  • 4
On our wavelength
443 Views
Message 3 of 17
Flag for a moderator

Re: Telnet into pop server?

Yes, I discovered that by accident after coming here.?

However the question still remains?, can one telnet into mail servers anymore.?

We used to do it when I worked for NTL to remove large emails blocking the download of the rest of the emails before broadband?

Yes, that long ago. 🙂

 

0 Kudos
Reply
Graham_A
  • 16.54K
  • 2.32K
  • 7.07K
Very Insightful Person
Very Insightful Person
441 Views
Message 4 of 17
Flag for a moderator

Re: Telnet into pop server?

One of the other VIPs @ravenstar68 may be able to advise on that when he is next available.

________________________________
Graham

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media, I'm a VM customer. There are no guarantees that my advice will work. Learn more

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks

0 Kudos
Reply
WelshGasman
  • 38
  • 0
  • 4
On our wavelength
436 Views
Message 5 of 17
Flag for a moderator

Re: Telnet into pop server?

Well it was just part of the debugging process to find out where the fault was?

However would still like to know as it appears not?

Thank you.

0 Kudos
Reply
ravenstar68
  • 19.4K
  • 1.14K
  • 8.46K
Very Insightful Person
Very Insightful Person
427 Views
Message 6 of 17
Flag for a moderator

Re: Telnet into pop server?

You don't say what server you're trying to telnet into.  Remember telnet ONLY supports plain text connections.  If a server expects an SSL connection it will hang once you get in as it waits for the client to negotiate a secure connection.

If you are trying to access pop3.virginmedia.com it only supports secure connections on port 995.

There's two ways to get in.

Install openssl and use the following command:

openssl s_client -connect pop3.virginmedia.com:995

OR

install and set up stunnel to tunnel a connection from localhost port 110 to pop3.virginmedia.com port 995

The advantage to the latter is that s_client ONLY gives you 10 seconds to input your first command before closing the connection (although once the first command is entered, that limit is gone).

Tim

Edit - Telnet should still work on pop.ntlworld.com port 110 but seriously I don't recommend it as you are sending your credentials across the net in plain text.

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks

WelshGasman
  • 38
  • 0
  • 4
On our wavelength
422 Views
Message 7 of 17
Flag for a moderator

Re: Telnet into pop server?

Thank you Ravenstar68.

That will be it the SSL connection.?

I was trying to telnet with port 995.

In my day it was 110 and so would work? 🙂

I was just trying to telnet to pop.ntlworld.com which now I find should not even be used? 😞

This was merely to see why my mail had stopped today. Turned out to be that recent: issue that is affecting a lot of people.?

0 Kudos
Reply
ravenstar68
  • 19.4K
  • 1.14K
  • 8.46K
Very Insightful Person
Very Insightful Person
413 Views
Message 8 of 17
Flag for a moderator

Re: Telnet into pop server?

From a  standards viewpoint it's been recommended that people DON'T send their credentials over plain text since 1997 as it can be intercepted by hackers.

So no I wouldn't recommend simply using telnet to pop.ntlworld.com on port 110 any more.  Installing stunnel should be fairly easy for someone such as yourself.  The default configuration file contains example connections for gmail POP3, IMAP and SMTP.  I simply amended the config to point to VM's servers instead.

Tim

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks

WelshGasman
  • 38
  • 0
  • 4
On our wavelength
395 Views
Message 9 of 17
Flag for a moderator

Re: Telnet into pop server?

I've never heard of stunnel.?
I must admit I do not keep uptodate that much anymore.

The telnet was just to see if the server was working?, as part of the debug process to find out why my email was no longer working?

It worked on webmail, so I suspected the pop server and know that they can go down now and again. My sister is always calling me with the sky server and I try and explain that they can go down, no matter how infrequently. 🙂

That was just me trying to see if I could at least get in to it.
Just tested with 110 and still works. 🙂

I have removed he recent: prefix from both my ntlworld and virginmedia addresses, so will see how it goes.

Thanks again.

0 Kudos
Reply
ravenstar68
  • 19.4K
  • 1.14K
  • 8.46K
Very Insightful Person
Very Insightful Person
382 Views
Message 10 of 17
Flag for a moderator

Re: Telnet into pop server?

stunnel can be found here.

https://www.stunnel.org/downloads.html

I run it as a service in Windows with the following config file

 

[VM-pop3]
client = yes
accept = 127.0.0.1:110
accept = ::1:110
connect = pop3.virginmedia.com:995
verifyChain = yes
CAfile = ca-certs.pem
checkHost = pop3.virginmedia.com
OCSPaia = yes

[VM-imap]
client = yes
accept = 127.0.0.1:143
accept = ::1:143
connect = imap.virginmedia.com:993
verifyChain = yes
CAfile = ca-certs.pem
checkHost = imap.virginmedia.com
OCSPaia = yes

[VM-smtp]
client = yes
accept = 127.0.0.1:25
accept = ::1:25
connect = smtp.virginmedia.com:465
verifyChain = yes
CAfile = ca-certs.pem
checkHost = smtp.virginmedia.com
OCSPaia = yes

 

With this in play I simply type in

telnet localhost 110 and stunnel picks up the connection and makes a connection to smtp.virginmedia.com port 995 SSL/TLS

Likewise telnetting to localhost 143 and localhost 24 gets me imap.virginmedia.com on port 993 and smtp.virginmedia.com on port 465

It's the first thing I use when I'm testing the servers.

Tim

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks