vpnc on cygwin 


Latest News

 04/24: The changes made against version r164 have been integrated and are available in the SVN repository as of version r169

 04/05: Some changes have been made against version r164. Please check here for details. Patch is vpnc-r164.diff 

02/04: The patches below have been integrated with the main code, therefore tap and Cygwin (w/ OpenVPN Win32 Tap device) support is available in the SVN repository as of version r113.


vpnc is a  VPN client created by Maurice Massar  which can connect to a Cisco3000 VPN Concentrator (http://www.unix-ag.uni-kl.de/~massar/vpnc/). Although it runs on many Unix-like OSes such as Linux, NetBSD, FreeBSD, OpenBSD, and Solaris, it does not run on Microsoft Windows 2000/XP.

Since I always wanted vpnc to run on a Microsoft Windows XP system, I've spent some of my spare time to modify some source code and come up with a version that works under Cygwin (http://www.cygwin.com/)


The changes were made against vpnc-0.3.3 and Win32 TAP-driver provided by openvpn-2.0.9 (http://openvpn.net/)

Diffs against vpnc-0.3.3: vpnc-0.3.3.diff.gz
Diffs against Win32 TAP-driver: tap-win32.diff.gz


(Jan 16, 2007): Diffs against vpnc's svn trunk (r92): vpnc-cygwin-r92.diff (includes tap-win32 directory)

(Jan 25, 2007): a modified Win32 TAP driver is not needed anymore! The diffs in vpnc-trunk-95.diff make vpnc work with TAP interfaces as well (tested under Linux 2.4 and Cygwin on WinXP w/ original OpenVPN Win32 Tap driver. Other OSes require additional support!)


 Everything is already in vpnc-0.4.0!!

(Obsolete) Complete Source code: vpnc-0.3.3-cygwin-20070109.tar.gz
(Obsolete) Compiled OpenVPN-compatible Win32 TAP-driver (compiled for Windows XP): tap-win32-bin.zip

Installation (for reasonable experienced people)

  • You need Cygwin (with all the common cool *nix tools) and libgcrypt installed
  • Download source code, ungzip, untar, cd into vpnc's directory, type make install
  • Unzip compiled TAP-driver, follow instructions in tap-win32-bin/driver/README
    Update: use OpenVPN original Win32 Tap driver if you are using vpnc-trunk-95.diff or svn version >= r113
  • edit /etc/vpnc.conf and /etc/vpnc-networks as needed


  • By default vpnc is installed in /usr/local/sbin
  • --no-detach is mandatory
  • if you are using vpnc-trunk-95.diff,--iftap is mandatory
  • if you are using a version from the svn repository (version >= r113), --ifmode tap is mandatory
  • svn version r113 does not support the vpnc-networks file (hopefully the support for client-supplied routes will come soon) 


  • TBD


Since I am busy at work I can only provide no to limited support, sorry!


paolo dot zarpellon at gmail dot com 

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