Deploying the Web Update Wizard

As discussed in the Web Update Wizard architecture page, you can deploy the Web Update Wizard as a Windows Service, or as a standard Windows executable.

Both implementations have the same functionality, with the exception that when the Web Update Wizard runs as a Service it runs in the SYSTEM security context, and therefore has rights equivalent to Administrator rights to update any files on the host computer, even files which the logged on user does not have rights to change.

(Note that Windows 98ME does not support running Windows services, so if you still need to support Windows 98ME you will be forced to use application mode for the Web Update Wizard. See here for a Windows 98ME strategy.)

The easiest deployment option - use our supplied redistributable installer, wuwinstaller.exe

Installing using wuwinstaller.exe:

The easiest way to deploy the Web Update Wizard is with the supplied wuwinstaller.exe, which is located in the 'WebUpdateWizard' folder under 'Program Files on your computer.

You can launch this installer from within your own application installer. You can force it to run silently (i.e. with no user interface) by passing the text "/S" as a command line argument, as in:

In common with most modern installers, wuwinstaller.exe needs to be run by a user with Administrator rights, because it installs files into the "Windows\System32" folder and endeavours to install/start a Windows service (the Web Update Wizard service).

You have already 'seen' wuwinstaller.exe in operation, as the developer installer used it to install the Web Update Wizard service and core components onto your computer.

Wuwinstaller.exe contains the following core Web Update Wizard components, and installs them into the System32 folder underneath Windows:

WebUpdateSvc4.exe - the Web Update Wizard service application
WuWUI.exe - the Web Update Wizard User Interface (UI) component
wuw4.dll - the Web Update Wizard dll, whose exported functions your application calls to initiate update checks
wuwuninst.exe - uninstaller program for the Web Update Wizard redistributable

In addition, wuwinstaller.exe installs and starts the Web Update Wizard service application, which you can verify via the services.msc applet.

Uninstalling using wuwinstaller.exe

To uninstall the core components on a client machine your uninstaller should call 'wuwuninst.exe', which the installer installed into the user's 'System32' folder.

As with wuwinstaller.exe, appending "/S" to the command line causes wuwinstaller.exe to work with no user interface, as in:

The wuwinstaller.exe redistributable takes care of shared file counting. In other words, each time wuwinstaller.exe is run it creates/increments a shared file counter in the Windows registry. Each time wuwuninst.exe is run the shared counter is decremented. When it reaches zero the shared files are removed. The registry key which contains the counter is:

HKEY_LOCAL_MACHINE\SOFTWARE\Web Update Wizard\InstallCount

We recommend that you use wuwinstaller.exe to deploy the Web Update Wizard because it removes your responsibility for installing and starting the service and ensuring that uninstalling your application does not intefere with other applications which depend on the Web Update Wizard for automatic updates. It adds only 275Kb of overhead to your installer.

If you decide to 'roll your own' installer then you will have to address all of the issues outlined above - i.e.:

Install and start the service on installation
Ensure when you uninstall your app it does not uninstall the Web Update Wizard unless no other applications depend on it
Stop and uninstall the service from Windows

Licence file location

However, if you really need to locate the licence file in a different folder, you may do so, and then pass the folder within the WebUpdate() or WebUpdateWait() URL, as shown here:

WebUpdate("http://www.mycompany.com/updatescript.txt|c:\Program Files\MyApp\LicenceFolder");

The folder path is appended to the update script URL and separated with a '|' character (ASCII character decimal 124 / hex 7C).

However - please note that if you use this option the default update folder (i.e. if you do not use a TargetFolder keyword) will be the folder you specified for the licence file. Also the <CLIENTFOLDER> folder substitution variable will return the folder you specified for the licence file.

Therefore, unless you have a compelling reason to deviate, we strongly recommend that you install WebUpdateSvc4.lic into the folder of your running application.

Service Control

See also: Web Update Wizard Service Reference for information on start-up parameters for the Windows Service implementation of the Web Update Wizard. However, If you use wuwinstaller.exe you do not need to know this information!

Adding Web Update Wizard to Your Own Installer?

We strongly recommend simply calling wuwinstaller.exe from within your own installer. As explained above, adding the command line argument "/S" will ensure the installation is silent and automatic.

Your uninstaller then calls the Web Update Wizard uninstallation program which wuwinstaller.exe will have installed into the user's System32 folder, 'wuwuninst.exe'.

Nearly every installer maker available allows you to launch additional processes such as wuwinstaller.exe as part of your installation. Whilst we are happy to provide the information below, we do recommend using our wuwinstaller.exe, because we have worked through the inevitable complexity associated with installing/uninstalling a potentially shared set of files, starting and stopping a Windows service etc..

However, if you are determined to incorporate the Web Update Wizard components individually into your own installer, this is what you will need to do: