When you deploy an application that uses ClickOnce technology over the Internet or over an intranet, a user on a client computer may click Install or Run on a published page. However, the Setup program does not respond. Additionally, the user does not receive an error message. When you try to install the ClickOnce application from the Web server, the Setup program runs as expected.

This problem occurs when you use the Internet Explorer versions that are listed in the "Applies to" section.

This problem occurs because the Internet Explorer security setting for the Run components not signed with Authenticode option under .NET Framework-Reliant Components is set to Disabled or Prompt. These settings prevent you from installing a ClickOnce application over the Internet or over an intranet, even if the component is signed.

To resolve this problem, obtain and install Microsoft .NET Framework 3.5 Service Pack 1 (SP1) or a later version. To obtain the .NET Framework 3.5 SP1, visit the following Microsoft Web site:

Important These steps may increase your security risk. These steps may also make the computer or the network more vulnerable to attack by malicious users or by malicious software such as viruses. We recommend the process that this article describes to enable programs to operate as they are designed to or to implement specific program capabilities. Before you make these changes, we recommend that you evaluate the risks that are associated with implementing this process in your particular environment. If you decide to implement this process, take any appropriate additional steps to help protect the system. We recommend that you use this process only if you really require this process.

Note The following work around should be used only when installation of .NET Framework 3.5 SP1 or a later version is not practical.

To work around this problem, set the Run components not signed with Authenticode option under .NET Framework-Reliant Components to Enabled in Internet Explorer. To do this, follow these steps:

1. Start Internet Explorer.
2. On the Tools menu, click Internet Options.
3. On the Security tab, click Custom Level.
4. In the Settings box, click Enable under Run components not signed with Authenticode.
5. Click OK, and then click Yes to confirm the setting change.
6. Click OK to close the Internet Options dialog box.

If you deploy a ClickOnce application to an intranet site, the Setup program depends on intranet security zone settings. If you are deploy the application to an Internet site, the Setup program depends on Internet security zone settings.

For more information about ClickOnce applications, visit the following Microsoft Developer Network (MSDN) Web site: For more information about how to use security zones, click the following article number to view the article in the Microsoft Knowledge Base: