Icon The Kermit Project   |   Now hosted by Panix.com
New York City USA   •   kermit@kermitproject.org
since 1981
The first new Kermit release for Windows in VERY nearly twenty years...

  CKW: C-Kermit 10.0 for Microsoft Windows

    THIRD BETA TEST: 15 September 2022

Download   Install   Run   Export   Coexist   Documentation   Problems   Screenshots

Also see:    CKW How-To   (Ini files, SSH setup, ...)     See daily progress notes 

Frank da Cruz
ckw@kermitproject.org ← questions, problems, reports
Created: 16 July 2022
CKW Beta date: 16 September 2022
This page last update: Wed Dec 14 06:29:21 2022 New York time

This page assumes a degree of familiarity with Kermit software; if you need an introduction, look HERE.

The new Open Source release of the Program Formerly Known as Kermit 95 — K95 for short — and which is now called C-Kermit for Windows — CKW for short — is closer to final release, thanks (once again) to David Goodwin in New Zealand, who has been working on it nonstop since July. His third Beta test version is available as of 15 September 2022. CKW Beta test numbers are slightly out of tune with C-Kermit's, which is still (as of the same date) Beta.04, so this one is called C-Kermit for Windows 10b4 Beta 3; it is built using C-Kermit Beta.04 sources plus a couple fixes described HERE in the 14 September 2022 section. If we have one more CKW Beta before the C-Kermit beta, we'll be back in sync!

By the way, it would also be appropriate to call C-Kermit for Windows "W-Kermit", which looks better than "CKW" in menus like the one at the top of this page, where "C-Kermit for Windows" is too long and "CKW" too short. Also W-Kermit follows the pattern of E-Kermit and G-Kermit, not to mention C-Kermit itself.

If you are experiencing problems with the screen cursor in Beta 03 (lagging behind, disappearing, etc) see Problem #3 below.

David's notes  •  What's new in Beta 3  •  SSH support in Beta 3  •  David's changelog  •  Previous Beta

The big news in CKW10b3 is that OpenSSL support has been resuscitated. This means that:

CLICK HERE for a complete list of new features in CKWb3, which also include SSH improvements, some screen and mouse improvements, etc.

David adds, "The SSH and SSL enabled build of CKW (ckw-b3.zip) requires the Visual C++ 2019 Redistributable - if it's not already installed you'll get an error of some kind probably complaining about a missing DLL. The latest version for Vista and newer is https://aka.ms/vs/17/release/vc_redist.x86.exe, while Windows XP Service Pack 3 is stuck at an older version (16.7) which is available from MSDN but as that requires a subscription I've put a copy of it here: https://ftp.zx.net.nz/pub/dev/redist/vcpp/2019_16.7/VC_redist.x86.exe."

Also the ex-K95 Dialer is included for the first time in this Beta:


Source code:

The dialer is packaged separately since the same version should run on all supported Windows platforms except for NT 3.50. Anyone wanting to use it can just put the dialer files into the same directory with the CKW Beta 3 files and the dialer button on the CKW toolbar should be enabled and everything should pretty much work as it did in Kermit 95.

I hope that CKB's revived support for secure Telnet, FTP, and HTTP connections will encourage the redeployment of secure Telnet and FTP servers around the Internet, since Kermit's client implementations are vastly superior to the SSH regime in power, flexibility, features, customizability, automatability, and user-friendliness.

About C-Kermit for Windows

As noted in the table above, the source code is available from David's archive. It will be incorporated into the C-Kermit 10.0 Beta.05 sources (along many other contributions and fixes) and then everybody should be sync. The third CKW Beta announces itself as:
C-Kermit 10.0 OPEN SOURCE: Beta.04/Windows-03, Sep 15 2022, for Windows
 Copyright (C) 1985, 2022,
  Trustees of Columbia University in the City of New York.
Type ? or HELP for help.
The copyright remains with Columbia U, in accordance with the separation agreement of 2011. CKW uses the C-Kermit version number, not the old K95 one, which was different (the last K95 release was 2.1.3, which was contemporary with C-Kermit 8.0.207). The LICENSE command shows the new Open Source license.

Known Problems with C-Kermit for Windows Third Beta

Send bug reports, questions, and comments to ckw@kermitproject.org.
  1. CKW's SSH client, which is based on LibSSH 0.10.3, does not interoperate with ancient SSH servers even when they support the same SSH version, (V2), key formats (e.g. RSA, DSA, ed25519), and ciphers. For example, one such host has OpenSSH 5.3 which was originally released nearly 13 years ago. Administrators of such hosts are encouraged to install a newer OpenSSH server because older ones have vulnerabilities. Meanwhile David says "In beta 3 I upgraded from libssh 0.9.6 (which was the latest version at the time beta 2 was released) to libssh 0.10.3. I was a bit surprised to hear beta 2 worked so I went digging in the libssh change log and I wonder if this is the cause:
    Disabled DSA support at build time by default (will be removed in the next release)
    Perhaps beta 2 was only able to connect because libssh 0.9.6 still supported DSA. I might have a go at doing a build of libssh 0.10 with it re-enabled as David Hittner got back to me saying he'd hit the problem connecting to an OpenVMS box. In the meantime grabbing ssh.dll from beta2 seems to work." CKW users can work around the problem by using an SSH relay.
  2. K95's SSH client, which is built on the LibSSH DLL, transfers files correctly but much slower than expected. For example on an SSH connection from CKWb3 (or CKWb2) to Ubuntu, a 19MB PDF file transferred at at 583663cps. The same file on a Telnet connection to the same host transferred at 10029471cps: 17 times faster. Progress: the next CKW Beta will have transfer rates at least 10 times faster; you can try it here if you wish.
  3. Management of the blinking terminal cursor in the third Beta is a bit off; for example if you type fast the cursor might disappear while you're typing. There is already a fix for this; you can try it by downloading a slightly newer version of CKW Beta-03, which differs from the original Beta-03 only by the blinking-cursor fix and the date (19 September instead of 15).
  4. If you download a file to CKW whose name contains accented or non-Roman characters (for example "Grüße" in ISO Latin-1 or UTF-8), the file will arrive but its name will be garbled, as (in this example) "GrüÃ\237e". This has been true forever; the fault lies with both Kermit and Windows. Kermit has no way of specifying the character set of the filename, and Windows does not support any character sets except "ANSI", "UNICODE" (i.e. UCS-2), UTF-8, and UTF16-LE. "ANSI" (an egegious misnomer) indicates Windows Code Page CP-1252. The fact that the filename (in this case) was already UTF-8 — which Windows supports — is no help because Windows doesn't know that, and so converts it from whatever it thinks it is into something else. Anyway, long story short: It is always safest to give files names that are spelled with ASCII letters A-Z and digits 0-9 and a few other characters like "-" (hyphen), "_" (underscore), and of course "." (period). Almost anything else can cause confusion or conflict. And avoid including spaces in filenames even if it's legal. And for that matter don't assume that capital and small letters are equivalent in filenames; they are in some operating systems but not others.
  5. If you already had Kermit 95 installed on your computer, then after you install CKW, if you edit \v(inidir)k95custom.ini* or \v(inidir)k95site.ini, CKW will not see your edits . This turns out to be for two good reasons:
    1. Your k95custom.ini (your personal customization file) file should be in \v(appdata), not \v(inidir).
    2. \v(k95site.ini) is not for personal use, it's for the network manager on PC networks to make site-wide customizations, e.g. for all the PCs on a corporate PC LAN.
    Diagnosis: All these directories were writable by the user in early Windows versions. Beginning with (I think) Windows Vista, \v(inidir) became read-only except for Administrator. The reason the problem became evident only in CKW B2 is that it's the first version to be built with modern compilers and runtimes.

    Solution: Moving k95custom.ini to \v(appdata) — where you can edit it — fixes the problem.

  6. Alt-n is supposed to let you enter any Plane-1 Unicode value as four hexadecimal digits, but:
    • it only accepts 3 digits;
    • when you type the fourth digit CKW disappears instantly;
    • So there's no way to enter Unicode characters that are otherise typeable.
    Example: lowercase dotless i: 'ı' (as in Turkish): Alt-n 0131 should work but typing the final '1' kills CKW.
* \v(inidir) is normally "C:\ProgramData\Kermit 95\" but might be something else on older Windows versions.


The third Beta-test version is available as of 15 September 2022, downloadable in various configurations from here:


The configurations are:

Table 1: CKW download options; source: https://ftp2.zx.net.nz/pub/CKW/test_builds/2022-09-15/README
Configuration package link  Description
ckw-b3.zip Full-featured version for Windows 11, 10, 8.1, 8, 7, Vista, and XP Service Pack 3. Includes SSL, SSH, and Pseudoterminal code

You will need to install the Visual C++ 2019 Redistributable if you don't already have it. You can grab the latest version of this for Windows Vista and newer from https://aka.ms/vs/17/release/vc_redist.x86.exe.

On Windows XP, the last version of the redistributable is 16.7. You can get it from here: https://ftp.zx.net.nz/pub/dev/redist/vcpp/2019_16.7/VC_redist.x86.exe.

ckw-b3-vintage.zip Feature-reduced version for Windows NT 3.51, 4.0, 2000, Windows XP pre-SP3 OR Windows 95, 98, ME. Does NOT include SSH, SSL, or PTY support and is intended only for vintage Windows systems which have known security issues.
ckw-b3-nt350.zip Special feature-reduced version of C-Kermit for Windows NT 3.50 only. The use of this one on newer systems is not recommended.
ckw-b3-src.zip CKW C-language source code.

Here's the procedure:

  1. Make a new folder on your desktop named (you can name it whatever you want, but the following instructions refer to ).
  2. Download the desired CKW configuration package from the "Configuration column package link" column in the table. The appropriate choice for most people (i.e. those using Windows Vista or later) would be ckw‑b3.zip (we'll assume this in the rest of the instructions).
  3. Move (drag) the downloaded zip archive to folder.
  4. Open (double-click) the folder.
  5. Right-click on the .zip file and choose "Extract All...". This creates a subdirectory called .
  6. (optional) Delete the .zip file (right-click → delete).


There is (as yet) no "one-click" installer for CKW. Here is the procedure for the second and third Beta. A distinct advantage of the current do-it-yourself method is that, not only can you have CKW and K95 installed at athe same time, you can also have multiple versions of CKW on your PC. Case in point: there is a host that I use on a daily basis that has an antiquated SSH server. The second Beta worked with it, but the third did not because it is built with a newer version of LibSSH, which has dropped support for old SSH servers. Anway, here is the installation process for the current Beta:
  1. Open the "" folder (double-click it).
  2. The folder contains 26 files, which include:

    • k95g.exe - The executable C-Kermit 10.0 for Windows (K95) program
    • k95.exe - Ditto, but runs in "console mode" (like DOS, not recommended)
    • libcrypto-1_1.dll - Required for SSH
    • ssh.dll - Required for SSH
    • libssl-1_1.dll - Required for SSH
    • And a bunch of others that can be ignored
    The DLL's are required for Kermit to run, so don't delete them.
  3. If you already have an icon on your desktop called "k95g.exe - Shortcut" from the previous CKW test version, rename it (for example to "k95gB1.exe") so you can still have access to to Beta 1. Ditto for Beta 2, Beta 3, etc.
  4. In the " folder, Right-click on k95g.exe and choose "Create shortcut". This creates a file called "k95g.exe - Shortcut" in the same folder.
  5. Drag the "k95g.exe - Shortcut" to your Windows desktop or wherever else you want to run Kermit from. Recommend you rename it to something like ckwb3.exe so the name doesn't wrap around or get lost on crowded desktops.
Leave the folder as it is, don't move, rename, or delete it.

The new built-in SSH client is ready to use for password authentication. To set up passwordless key exchange authentication, read these instructions.


Start (run) the new C-Kermit for Windows program by double-clicking the icon you just made in the previous step. The first time you start it you'll get warnings from Windows and/or your antivirus software because this is a new program and it's free and open-source. Examples of warnings:

  1. Windows protected your PC
    Microsoft Defender SmartScreen prevented an unrecognized app from starting. Running this app might put your PC at risk.
    More info click this
    App:  k95g.exe
    Publisher:  Unknown publisher
    [ Run anyway ] ← click this
    (see screenshot)
  2. Symantec Endpoint Protection Download Insight
    Our information on this file is inconclusive. We recommend not using this file unless you know it is safe.
    [ Remove this file from my computer ]
    [ Allow this file ] ← click this
    Unproven: There is not enough information about this file to recommend it. Very few users: This file has been seen by fewer than 5 Symantec users. Very new: Symantec has known abou this file approximately 2 days.

    Permission: If you press OK, an application exemption will be created for this file. You should allow only files you are sure are safe. Are you sure you want to allow this file?
    [ Cancel ]
    [ OK ] ← click this
These warnings appear only the first time you start the new CKW. But they come back when you download a new release (and then they go away again).

Coexistence with K95 2.1

If you already have Kermit 95 2.1.3 (or earlier) installed on your PC, CKW won't interfere with it and you can use both versions, and you can still use the K95 Dialer. At present CKW is installed in a folder on your desktop, whereas K95 2.1 was installed in the normal Windows way:
Table 2: K95 2.1 directories
File Filename Directory Kermit variable
Executable (GUI) k95g.exe C:\Program Files (x86)\Kermit 95 2.1\ \v(exedir)
Executable (console) k95.exe C:\Program Files (x86)\Kermit 95 2.1\ \v(exedir)
Root startup file k95.ini C:\ProgramData\Kermit 95\ \v(inidir)
Sitewide initialization file k95site.ini C:\ProgramData\Kermit 95\ \v(inidir)
Customization file k95custom.ini C:\Users\username\AppData\Roaming\Kermit 95\ \v(appdata)
Note: the actual directory names can vary according Windows version.

CKW *presently* uses the same initialization and customization files. If these files contain any commands not supported by CKW or by K95, you can protect them with:

if < \v(version) 1000000 {
    commands for K95    
if >= \v(version) 1000000 {
    commands for CKW
\v(version) is the all-numeric version number of the C-Kermit code used for the Windows build. 1000000 is C-Kermit 10.0 and 800207 is C-Kermit 8.0.207. When CKW is finally released it will still peacefully coexist with K95, although the exact mechanisms have yet to be worked out, but most likely all of its file names will start with "ckw" rather than "k95" (as in the table), and it will have its own separate \v(exedir), \v(inidir), and \v(appdata) directories.

The CKW Initialization File

More about "Ini files"

In Betas 1 and 2 CKW uses K95's initialization and customization files (Table 2) if they exist. Future Betas will have their own set, e.g. ckwcustom.ini instead of k95custom.ini. The same directories as for K95 are used for the k95.ini, k95site.ini, and k95custom.ini files. These are plain-text files that contain C-Kermit/CKW commands. The k95custom.ini is where you would set up your preferences. For making connections to other computers, you can define a macro for each host includes the access details, the connection and login procedure, and the fonts, font-sizes, screen dimensions, colors, position, resize behavior, and so on, for each host you connect to. You can use different attributes (e.g. color) for each host so when you have many connections going at once, you can tell the difference by their distinct appearances. The K95 Relay page includes an example of such a script. New scripts and ini files for CKW will be posted here shortly.

Exportability of SSH client

The US Department of Commerce Bureau of Industry and Security (BIS) Export Administration Regulations (EAR) govern the export of software that includes encryption features. These rules have changed since Kermit 95 was last released in 2003, at which time certain countries were barred from obtaining such software from the USA by mail order, download, or other means. As of 2021, however, Kermit software is no longer subject to export restrictions, and C-Kermit for Windows can include a built-in SSH client based on LibSSH that is, indeed, exportable to all countries. See these references:
  1. Understanding US Export Controls with Open Source Projects, The Linux Foundation
  2. Understanding US Export Controls and Open Source Projects (2021 Update), The Linux Foundation
  3. Publicly Available - Public Domain - Open Source, MIT Office of the Vice President for Research
  4. Bureau of Industry and Security Export Administration Regulations, US Department of Commerce (2022)
  5. Bureau of Industry and Security Commerce Control List Category 5 - Telecommunications and Information Security

In brief (paraphrasing from item 5):  Publicly available ready-to-use software whose primary function is other than information security, that includes an openly available encryption component without modifications, and that is of interest to a wide range of individuals and businesses, is exempt from the BIS Export Administration Regulations. That's why LibSSH and numerous SSH clients are downloadable on the Internet by anybody at all, no matter what country they are in. CKW will be no different.

Similar considerations apply to Kermit's built-in OpenSSL and Kerberos 5 features, such as its Telnet, FTP, and HTTP clients.


Specific to C-Kermit for Windows:
A "How To" document for getting started with CKW:

David Goodwin's notes:

Since C-Kermit for Windows is C-Kermit, you can refer to the C-Kermit documentation for most everything else:
For an introduction to the Kermit script language (which lets you write procedures to automate common tasks), see this page:
For CKW's Windows-specific aspects, see:
  1. Chapter 6 of the Kermit 95 manual: Using the Command Screen,
  2. Chapter 7 of the Kermit 95 manual: Using the Terminal Emulator, and
  3. Chapter 8 of the Kermit 95 manual: File Transfer.

The New Open-Source Kermit Project hosted by Panix.com