Enabling/disabling add ons in IE during test run

I have to test functionality where a video archive on a web site has to be played with Windows Media Player and then with a Silverlight player. If the test were manual, the tester would first see if the video is player with WMP, then go to Tools->Manage add-ons, enable Microsoft Silverlight, close the Manage add-ons window and test to see if the video can be player with Silverlight.

Is it possible to simulate these actions within a script? If it is possible how would I do that? Thank you.