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I'm running Windows 8.1 Pro Preview. For some strange reason whenever I visit with the Desktop Version of IE11 Preview (11.0.9431.181), I get prompted with this message:
"This webpage wants to run the following add-on: 'npctrl.dll' from 'Microsoft Corporation'."

When I Bing around to find the purpose of the DLL, I seem to discover various links like this one implying that the DLL is somehow related to Silverlight:

Please forgive me if I am wrong, but I thought that:
a) Silverlight was 'dead'?
b) SkyDrive was rewritten to use HTML5

So if Silverlight is "dead" and SkyDrive uses HTML5, why does SkyDrive want me to activate a "Silverlight" "plugin" when I visit?

BTW: Neither FireFox 22.0 nor the Modern UI Version of IE seem to prompt me when I visit SkyDrive in a similar manner.

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First link is somewhat of an opinion, not a fact. Remembered reading something in the likes of that - Silverlight veered of it's path. Second makes sense, since you can run in Firefox, so Skydrive should be running in HTML5 mode. Since IE comes from Microsoft (and you stated you were using a non up-to-date version), it still must be using some connection to Silverlight. – Doktoro Reichard Aug 21 '13 at 3:31
up vote 1 down vote accepted

Ok, facts be facts. First one comes from Wikipedia and quoting:

On December 2, 2008 ... Microsoft also added full-screen slide show support for photos using Silverlight.

First and only mention of Silverlight in that page. This means that SkyDrive has used Silverlight for a long time, maybe from the start. Since Wikipedia doesn't have a source on this it can't be 100% certain.

Second comes your link. I also found this post that describes a similar problem with Silverlight and Skydrve.

If you look at the Silverlght stable release date (July 9, 2013) you can see that it is still actively developed. In response to your first question, Silverlight is not dead by this reasoning.

Now, it is true Silverlight is being abandoned in favour of HTML5. However, Skydrive was build previously with Silverlight in mind. So, some remnants of Silverlight code must still be there, as it isn't logic, from a developer standpoint, to ditch all work made and suddenly pass on to HTML5. Most likely it will be a gradual obsolescence cycle. Since IE is from Microsoft, it is bound to favor it's products. This answers your second question, adding what I said in the comment.

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yes, MS still uses silverlight in a number of places on online. If you use any of the dev portals they still use a silverlight based video player. – roryok Aug 21 '13 at 13:23
I do see a lot of those on "old" Office 2010 help pages, another reason why Silverlight isn't really dead (although I would attribute that to laziness) – Doktoro Reichard Aug 21 '13 at 13:43

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