How to: Set a security zone for a ClickOnce application
Applies to: 
Visual Studio 
Visual Studio for Mac
Note
This article applies to Visual Studio 2017. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here
When setting code access security permissions for a ClickOnce application, you need to start with a base set of permissions on the Security page of the Project Designer.
In most cases, you can also choose the Internet zone which contains a limited set of permissions, or the Local Intranet zone which contains a greater set of permissions. If your application requires custom permissions, you can do so by choosing the Custom security zone. For more information about setting custom permissions, see How to: Set Custom Permissions for a ClickOnce Application.
To set a security zone
With a project selected in Solution Explorer, on the Project menu click Properties.
Click the Security tab.
Select the Enable ClickOnce Security Settings check box.
Select the This is a partial trust application option button.
The controls in the ClickOnce security permissions section are enabled.
In the Zone your application will be installed from drop-down list, select a security zone.