Open a test TCP connection to a specified IP/Port

Netcat

nc mail.server.net 25

Socat

socat - TCP4:www.domain.org:80

(Windows version)

Reading socat's examples page never fails to boggle my mind.

pkgmgr is now replaced by dism.

Install telnet from command line (run it as administrator):

dism /online /Enable-Feature /FeatureName:TelnetClient

Then you can test TCP connection by:

telnet example.com 80

Just use Putty it's tiny (and has a portable app version). It lets you specify port and can use telnet which is a TCP connection. It also has other useful functions like serial connections (no hyper terminal in Windows 7), SSH, And Rlogin. It even has a RAW function that lets establish RAW TCP connections.

Also just so your aware: Telnet is included in XP, you can use it from the command line IE:

telnet mailserver.server.com 25

Which would establish a TCP connection on port 25.

We used to telnet to a certain port, but telnet does not come with windows 7 anymore by default. So for your USB stick: http://www.drk.com.ar/builder.php

There used to be telnet in Windows, not sure if that's been removed in later versions. Try looking for it.

You could download Cygwin and run the utilities in there, including netcat and telnet.

There is a Windows version of NetCat available, but I didn't see a canonical URL for it, so I did not include a specific one.