A ClickOnce application or a WPF XAML browser application displays no notification that asks whether you want to run the application when you try to run the application in the Internet Zone in Internet Explorer
The signature-verification process for ClickOnce applications and for WPF XBAPs is updated to help you recognize when you are running untrusted applications from the Internet Zone. After you install the MS11-044 security update, you see an Application Run dialog box that is typically encountered when you use Internet Explorer to access an application over the Internet.
If existing ClickOnce applications or WPF XBAPs are expected to run from the Internet in online-only mode without dialog boxes being presented, changes may have to be made to those applications for the applications to continue to run correctly after MS11-044 is installed.
To revert to the application's start behavior after you install the update, use one of the following methods:
Add a trusted publisher
Add a trusted site
How to add a trusted publisher
Obtain a digital certificate from a certification authority (CA). For more information about how to obtain a digital certificate, visit the following Microsoft Developer Network (MSDN) website:
In addition to the changes that are listed in the "Vulnerability Information" section of bulletin MS11-044, this security update also deprecates ClickOnce support for MD2 and MD4 hash. After the update is applied, applications that are signed with an MD2 or MD4 hash will no longer run.