Member Avatar for HarryMagig

Basically, I cannot connect to anything using the telnet software that comes with Windows. I have enabled the telnet service and I can't work out what's causing it so I'm wondering if you guys could help. I'm using Windows XP and the error message I get is:

Could not open connection to the host, on port 23: Connection failed
  • 3 Contributors
  • 12 Replies
  • 3K Views
  • 6 Years Discussion Span
  • Latest Post Latest Post by fallout4player

Dani AI

Generated

A couple of quick clarifications that should help and others reading this later. You do not need the Windows Telnet service (TlntSvr) enabled to make outgoing tests; that service only accepts inbound logons and is best left off because Telnet transmits everything in plaintext. Use the Telnet client for one-off port checks and prefer SSH or other secure tools for remote access. Microsoft has long treated Telnet as insecure and deprecated the server component. (learn.microsoft.com)

About the “black screen” when you telnet to port 80: that usually means you are connected but your keystrokes are not echoed locally. In the Windows Telnet client, press Ctrl+] to reach the telnet prompt, enable echo, then try a simple HTTP request:

telnet
set localecho
open example.com 80
GET / HTTP/1.0

After the blank line, you should see an HTTP response if the connection is good. You can turn echo back off later with unset localecho. (learn.microsoft.com)

As hinted, ping success does not prove a TCP port is open; ping uses ICMP at the IP layer. To test a specific port, use Telnet as above, or on newer Windows use PowerShell: Test-NetConnection host -Port 23. (learn.microsoft.com)

Two notes tailored to this thread: (1) LOCIS was retired years ago, so connection failures there are expected; the Library of Congress ended search access to LOCIS on January 11, 2000. (guides.loc.gov) (2) For ’s Star Wars nostalgia: public Telnet services can be intermittent or blocked on some networks. If you only want to watch the ASCII animation, there is a web version maintained by the original creator. Alternatively, for testing Telnet/SSH in general on modern Windows, a safer client like PuTTY is handy. (asciimation.co.nz, chiark.greenend.org.uk)

Recommended Answers

All 12 Replies

Member Avatar for techsheaven

Is this inside your local area network, or remote?

Edited by techsheaven because: Errata
Member Avatar for HarryMagig

I'm using BT and I'm trying to use remote. Is there anyway to stop them blocking it?

Member Avatar for techsheaven

Sorry about my last post 23 should be open. It is port 25 that ISPs are blocking.

You are using a CMD prompt in XP? can you ping the site?

Member Avatar for techsheaven

Port 23 is TCP port. Try 80 for telnet

Member Avatar for HarryMagig

Yeah I'm using Command Prompt on XP. I can ping this site fine but when I try telnet on port 80 on this site, the screen goes completely black and I can't type anything.

Member Avatar for techsheaven

On the server end the port must have been changed from the default.

Member Avatar for HarryMagig

Do you know any sites that work that I could try it out on. I tried it on LOCIS (The Library of Congress Information System) but I only get the message saying it could not connect, on both 23 and 80.

Member Avatar for techsheaven

telnet 13

This will give you the UTC time, date and then disconnect (port 13).

If you are just experimenting why not try your own mail server? I don't know who BT is, but you can find the ports that corrispond to their SMTP an POP3 servers usually 25 and 110.

Member Avatar for HarryMagig

Yeah that worked. Maybe the LOCIS isn't up and running anymore. Thanks for the help!

PS. BT is an ISP here in the UK. It stands for British Telecom.

Member Avatar for techsheaven

Glad I could help. Don't forget to mark the thread as solved.

Member Avatar for HarryMagig

Will do!

Member Avatar for fallout4player

I'm trying to make star wars work. telnet. cannot start connection lost port 23? what is thhhhhhis

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.