Windows - Software - Uninstall Microsoft Silverlight

What the Silverlight Uninstaller does

This Automox Worklet™ automatically detects and removes Microsoft Silverlight from Windows endpoints. Microsoft Silverlight reached end-of-support on October 12, 2021, and is no longer maintained or supported by Microsoft.

The Worklet checks both the 32-bit and 64-bit registry entries where software installations are tracked. It identifies any Silverlight version present on the endpoint and removes it using the application's built-in uninstall mechanism. The remediation process supports both MSI-based uninstalls and traditional executable uninstallers.

The Worklet examines registry keys including HKLM:\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall, HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall, HKLM:\Software\Microsoft\Windows\CurrentVersion\Uninstall. exe -ArgumentList "/x $($version.PSChildName) /qn", "Get-ItemProperty", and "Get-ChildItem".

This Worklet is particularly useful for organizations migrating away from legacy web technologies, consolidating their application portfolios, or enforcing security standards that prohibit end-of-life software.

Why remove Silverlight from your environment

Silverlight no longer receives security updates, bug fixes, or technical support from Microsoft, creating significant security risks for any endpoint that retains it. Microsoft Silverlight is a deprecated browser plugin that has been superseded by modern web standards like HTML5. Since reaching end-of-support in 2021, Silverlight exposes endpoints to unpatched vulnerabilities.

By removing Silverlight, you reduce your organization's attack surface and eliminate vulnerabilities that will never be patched. Also, removing legacy software improves system performance, reduces storage requirements, and simplifies your endpoint management and compliance auditing.

Modern web applications no longer require Silverlight. Organizations standardizing on HTML5 and contemporary web technologies benefit from improved compatibility, security, and performance across their endpoint fleet.

How Silverlight removal works

1. Evaluation phase: The Worklet scans both 64-bit and 32-bit registry locations in HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall and HKLM:\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall for any Silverlight installation entries. If any version is detected, the endpoint is flagged for remediation.

2. Remediation phase: If Silverlight is found, the Worklet executes the application's uninstall string from the registry. For MSI-based installations, it runs msiexec.exe with quiet mode flags. For executable-based uninstallers, it runs the uninstall command with the silent argument. The Worklet validates successful completion by checking exit codes and only logs successful removals.

Silverlight removal requirements

• Windows operating system (Windows Vista through Windows 11 and Windows Server 2008 or later)

• Local administrator privileges to access registry and remove installed software

• Microsoft Silverlight application installed on the endpoint (no action if not present)

• PowerShell execution policy configured to allow script execution

• No active applications using Silverlight plugins (remediation will not complete if Silverlight is in use)

Expected endpoint state after Silverlight removal

After successful remediation, Microsoft Silverlight will be completely removed from the endpoint. All Silverlight registry entries will be deleted, and the installation directories will be removed. The Worklet generates an activity log entry indicating successful uninstallation for your audit trail. This removal reduces your organization's attack surface by eliminating vulnerabilities that will never be patched.

You can verify removal by checking that Silverlight no longer appears in Control Panel's Programs and Features, and that registry keys no longer reference any Silverlight installation. Future evaluations of the Worklet will report compliance since Silverlight is no longer present on the endpoint, confirming consistent removal across your fleet.

How to validate uninstall microsoft silverlight changes

1. Run this Worklet on a pilot Windows endpoint and review evaluation output for uninstall microsoft silverlight.

2. Confirm Automox activity logs show successful completion and exit code 0.

3. Verify endpoint state using checks aligned to evaluation script logic, such as Write-Output, Get-ChildItem, Get-ItemProperty.

4. Validate remediation effects from script operations such as Test-InstalledSoftware, Get-ChildItem, Get-ItemProperty, then rerun evaluation for compliance.