"FAST PUBLISH" article: The Microsoft Silverlight add-on is listed as Not Verified in Microsoft Internet Explorer

You install Microsoft Silverlight in Internet Explorer 7 or later.  Next, you open the Manage Add-ons feature in Internet Explorer and view the Silverlight add-on information.  The publisher is listed as “(Not verified) Microsoft Corporation”.

This behavior occurs because while the installation package of Microsoft Silverlight is digitally signed, the add-on file npctrl.dll is not digitally signed. Internet Explorer checks the digital signature of the control’s binary file when it determines the publisher. If the signature is missing, the publisher information will be listed as “Not verified”.

This is a behavior by design.

The installation package of Microsoft Silverlight is digitally signed. This ensures the add-on is installed from an identified resource.  For more information, please see:
Internet Explorer add-ons: frequently asked questions

Note This is a "FAST PUBLISH" article created directly from within the Microsoft support organization. The information contained herein is provided as-is in response to emerging issues. As a result of the speed in making it available, the materials may include typographical errors and may be revised at any time without notice.


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