ClickOnce is a deployment technology that enables you to create self-updating Windows-based applications that can be installed and run with minimal user interaction. So in that case security is critical.
ClickOnce overcomes the following issues:
Difficulties in updating applications. With Microsoft Windows Installer deployment, whenever an application is updated, the user can install an update, an msp file, and apply it to the installed product; with ClickOnce deployment, you can provide updates automatically. Only those parts of the application that have changed are downloaded, and then the full, updated application is reinstalled from a new side-by-side folder.
Impact to the user's computer. With Windows Installer deployment, applications often rely on shared components, with the potential for versioning conflicts; with ClickOnce deployment, each application is self-contained and cannot interfere with other applications.
Security permissions. Windows Installer deployment requires administrative permissions and allows only limited user installation; ClickOnce deployment enables non-administrative users to install and grants only those Code Access Security permissions necessary for the application.
Consider if you are attempting to create a training game for a sales force and you need to update the game to reflect business requirements. ClickOnce will help you securely deploy these kinds of applications.
To determine your deployment scheme take a look at the following url:
Testing your Click Once is fairly easy, there are a number of free for 90 days hosting services for .NET based websites, and for the network if you have two computers you got it made.
Give it a try, you could actually make money off this if you set it up right.