Windows 10: Windows 10 1903 kills Silverlight LOB applications

We've run into a serious problem on PCs that have upgraded to Windows 10 1903.


Silverlight web applications are allowed to interact with local components provided two conditions:


A) The web application is signed with the same signing certificate that has signed the local component

B) The following registry keys are set to 1:


HKLM\SOFTWARE\Microsoft\Silverlight\AllowElevatedTrustAppsInBrowser

HKLM\SOFTWARE\Microsoft\Silverlight\AllowLaunchOfElevatedTrustApps

Starting with Windows 10 1903, a Windows operating system process, ccmexec.exe actively reverts any changes made to either of these registry key values. This has the effect of breaking Silverlight LOB (line of business) applications.

I can find no way to circumvent this, and the result will inevitably be disastrous and devastating for our internal and external customers using these applications as Win 10 1903 is deployed.

There is no Group Policy deployed in our org that would be involved in this new behavior, and this reversion is completely independent of Windows Defender process.

Any help or advice on turning off this active registry reversion "feature" would be appreciated.

Eric Helfgott

:)

 

Silverlight

Microsoft stopped developing Silverlight in 2012. Although it's still supporting Silverlight on Windows 10, for now, it's not supported on Microsoft Edge - you have to use Internet Explorer - and Google is either going to drop support for Silverlight or
already has. It's old technology.

Microsoft: We're not killing Silverlight in Windows 10, but stop using it anyway

 

Silverlight 5 Available for Download

Today, we’re happy to announce the release of Silverlight 5. Silverlight is part of a rich offering of technologies from Microsoft helping developers deliver applications for the web, desktop and mobile devices. Download Silverlight 5, a free plug-in less than 7 MB in size that can be installed in less than 10 seconds.

New features in Silverlight 5 include Hardware Decode of H.264 media, which provides a significant performance improvement with decoding of unprotected content using the GPU; Postscript Vector Printing to improve output quality and file size; and an improved graphics stack with 3D support that uses the XNA API on the Windows platform to gain low-level access to the GPU for drawing vertex shaders and low-level 3D primitives.

In addition, Silverlight 5 extends the ‘Trusted Application’ model to the browser for the first time. These features, when enabled via a group policy registry key and an application certificate, mean users won’t need to leave the browser to perform complex tasks such as multiple window support, full trust support in browser including COM and file system access, in browser HTML hosting within Silverlight, and P/Invoke support for existing native code to be run directly from Silverlight.

For more information, visit the Microsoft Silverlight site. For additional information on support policy, visit Microsoft Silverlight Support Lifecycle Policy.

The Silverlight Team

 

Microsoft Silverlight browser malfunction

Hi,

Issues related with Microsoft Silverlight are usually occurring due to corruption upon its installation. For us to provide an effective solution, we would need you to answer the following questions:

• Which build and edition of Windows 10 is installed on your device?
• What is the model of your laptop?
• Are you experiencing the same issue even when you are trying to access other websites?

In the meantime, we suggest following the steps provided in this link.
It serves as a guide on how to clean a corrupted Silverligh installation.

We are looking forward to your response.