VNC logo

Virtual Network Computing

AT&T

WinVNC - The Windows NT VNC server

WinVNC in system trayWinVNC is a VNC server that will allow you to view your Windows desktop from any VNC viewer. Because Windows in its present, standard incarnation, only supports a single graphical user being logged in at any one time, WinVNC makes the existing desktop of the PC available remotely, rather than creating a separate desktop as happens with the Unix server. It is only fair to emphasise this: VNC does not make an NT machine into a multi-user server in the same way that Citrix-based software, for example, does. A single NT machine can therefore be accessed by multiple users, but if they all connect at the same time they will all see the same desktop! 

On the other hand, WinVNC will run on Windows 95, Windows98, Windows NT 4.0, Windows 2000 and on any future Win32-based systems, without the need to replace any system files or run any OS-specific versions of the program. It is a standard application that can be run from the Start... menu and closed down just as easily. 

WinVNC can also be run as a service, which means that you can log in remotely, do some work, and log out again. We recommend that you run it in this mode. See below for more details.

And, of course, WinVNC is free. We hope that making the source code available will enable others to suggest improvements to any and all aspects of WinVNC.

Installation

WinVNC is simple to install and to use:
     
  1. Run the WinVNC setup program. (If you received VNC as a ZIP or TAR archive, you'll need to unpack it first!)
  2. Select Install Default Registry Settings from the WinVNC folder in the Start menu. This will install the default hooks settings, which are tweaked to cope with some common, uncooperative applications, such as the clock. This is not vital, but will make things run a bit better. See later for more information about the registry settings. 
  3. WinVNC can now be run (in Application mode) from the Start menu. Alternatively, you can use the Start->Settings->Taskbar menu to add a shortcut to your Startup group, which will cause WinVNC to be run every time you log in. NOTE: After some initial tests, we suggest you run WinVNC as a service instead of as an application. See below for more information.

Using WinVNC

On starting, WinVNC will add a small, green version of the VNC icon to the system task bar. Clicking on this icon with the right mouse button will cause a menu to be displayed, with the following options on it: Moving the mouse over the icon should cause the IP addresses of the local machine to be displayed, if they can be discovered at that time.

You can connect to the server from another machine using a VNC viewer, such as VNCViewer or PalmVNC.

WinVNC Properties

The following options are available from the Properties dialog.

Incoming Connections

Update Handling

Note that clicking in a window will generally cause it to be updated, so if you have certain applications which don't update very well, try this! The default update handling settings should be the right ones for most people, and in general you will slow things down by changing them, so don't do this unless you have applications which cause problems.

The user's settings are saved into the user-specific section of the registry when WinVNC quits, meaning that they will be used next time you run WinVNC.
 

Running WinVNC as a service

WinVNC can now be made to run as a service process under both Windows NT and Windows 95/98, by following the instructions outlined below. This allows you to connect to a machine which has nobody logged in to it, for example. On NT, you can also send Ctrl-Alt-Del to the server when it's running as a service, allowing you to unlock a locked workstation, for example. Note that in 'service' mode, many features are changed on a per-machine rather than per-user basis. You can access the per-machine 'Defaults' from the 'Administrative Tools' section of the VNC Start Menu group.  The following 'features' should also be pointed out:

Windows NT 'features':

Windows 95 'features': General features for both Windows NT and Windows 95: Here's how to get it running as a service, assuming you've already installed it.  Under Windows NT you need to have administrator privileges on the local machine, so log on as administrator if your account doesn't have these.
  1. Either:

    Select "Install WinVNC service" from the WinVNC Administrative Tools section of the Start menu.

    Or:

    Open a Command Prompt and run WinVNC with the -install option. eg:
    D:\> C:
    C:\> cd "\Program Files\ORL\VNC" 
    C:\Program Files\ORL\VNC> winvnc -install

  2. Windows 95 : The WinVNC service is now running and is installed to run whenever the system boots up into Windows 95.

    Windows NT : The WinVNC service is installed and set up to run whenever the machine is booted into Windows NT but IS NOT YET RUNNING! It will run when the machine next reboots. If you want to start it immediately, you can use the Services section of the Windows control panel, or "net start" from the command prompt:
    C:\> net start winvnc
    The service should now be running, but won't know that you are logged in until you log out and back in again. It won't yet appear on the taskbar. You can run the WinVNC Service Helper from the start menu to tell it who you are!

  3. If you wish to change the WinVNC settings (eg. password) when it is not visible on the taskbar, you can use Show User Settings from the WinVNC section of the Start menu. 
    If you wish to change the default settings used by the service when there's nobody logged in, or no user-specific settings in are use, use Show Default Settings from the Administrative Tools subsection of the WinVNC Start Menu. See below for more information about defaults.

    NOTE : Windows 95 : If Win95 has been set to use different settings for each user then the settings used are those of the currently logged in user.  If no user is logged in or Win95 is set to use the same settings for all users then the settings used are the Default user settings and are stored per-machine, rather than on a per-user basis as is done when running WinVNC normally.  (Under Win95, pressing Cancel on the login dialog gives access to the Default user settings.)

  4. When you wish to install a new version of WinVNC or simply wish to remove WinVNC from   your machine, you must first remove the service from the system, using the WinVNC Administrative Tools or the -remove command-line option.

    NOTE : A message about failure to remove the service usually indicates that it was not installed in the first place!

Command-line options

The full command-line options available are as follows. You probably won't need anything other than those listed above unless you're a real VNC power-user!

-run     
Causes WinVNC to run normally & ignore rest of command-line.
-install 
Installs the WinVNC service and continues reading the command-line.
-remove  
Removes the WinVNC service and continues reading the command-line.
-settings
Tells a running copy of WinVNC to show the User Properties box.
-defaultsettings
Tells a running copy of WinVNC to show the Default Properties box.
-connect host
Tells a running copy of WinVNC to initiate an outgoing connection to a listening viewer running on the specified machine. This is the equivalent of the 'Add New Client' menu option. You can put multiple -connect options on one command line to connect to multiple viewers at once.
-kill    
Kills a running copy of WinVNC.
-about   
Tells a running copy of WinVNC to show its About box.

If no options are given then WinVNC runs normally. Multiple options may be given, so, for example, to upgrade a currently running WinVNC service to a new version, you could use:
WinVNC_new -remove -install
which will stop & remove the old copy & install the new one as a service, or
WinVNC_new -kill -run
which will stop the running copy & run the new version as an application.

WinVNC - Advanced Settings

Extra options have been added to WinVNC for use primarily by system administrators, to tailor the server's behaviour to meet their particular needs.   The options are DWORD values which can be set in the system registry, and tools such as the Windows Policy Editor can be used to apply these settings across a large number of machines. 

Versions 3.3.2 R5 and later use a more sophisticated organisation of these options to allow more flexibility.   It also makes it rather complex, so we're thinking about alternative ways of doing this. WinVNC will currently look for settings in the following places:

     
  1. Local machine-specific settings. Options specified here are not overridable. Location:
    HKEY_LOCAL_MACHINE\Software\ORL\WinVNC3\
  2. Local default user settings. Location:
    HKEY_LOCAL_MACHINE\Software\ORL\WinVNC3\Default
  3. Local per-user settings.  These override the local default user settings. If there is no current user, the username SYSTEM will be used. Location:
    HKEY_LOCAL_MACHINE\Software\ORL\WinVNC3\<username>
  4. Global per-user settings.   These are only read if AllowProperties has not been set to zero (see below) Location:
    HKEY_CURRENT_USER\Software\ORL\WinVNC3
Most options can only be specified in a subset of these places, as specified in each option's description below.

Advanced Options:

VNCHooks - Advanced Settings

WinVNC uses a special library, VNCHooks, to hook into the other running applications and retrieve notifications of areas of the screen being changed.  The VNCHooks library uses the messages sent to visible Windows to decide which areas need considering for update. Not all applications use the same method of updating the screen, so you can tweak the method used by WinVNC for particular applications by editing the registry. All the entries listed can be found under

HKEY_CURRENT_USER\Software\ORL\VNCHooks\Application_Prefs

Running on other Win32 systems

WinVNC runs fine on NT3.51 but the absence of a system tray means that the Properties dialog cannot be accessed.  In addition, Ctrl-Alt-Del from clients cannot be correctly interpreted under NT 3.51, limiting WinVNC's usefulness when run as a service on this platform.  It also runs on NT5 beta. If you have a choice we recommend NT4.0 with the latest service packs installed.
 

Problems?

If you have difficulties which are not covered by this document, try reading the FAQ.  If that doesn't help then try the mailing list.
If you try to contact the developers directly, please remember that VNC has hundreds of thousands of users, and we cannot, in general, respond to individual queries. We will read your message, but don't expect an answer!