Unable to use WMEncoderLib.dll in my win forms project

I am trying to create a simple app that records the desktop screen for a minute and have downloaded and installed the wmencoder 9 series. In my project I am throwing an exception in the following line.

using WMEncoderLib;

private WMEncoder m_encoder = new WMEncoder();

The error says: "Retrieving the COM class factory for component with CLSID {632B606A-BBC6-11D2-A329-006097C4E476} failed due to the following error: 80040154 Class not registered (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG))."

I did some research and found that I have to register the dll using regasm in visual studio 2012 developer command prompt.

So I've tried :

C:\Program Files (x86)\Microsoft Visual Studio 11.0>regasm Interop.WMEncoderLib.dll

yielding:

RegAsm : error RA0000 : Unable to locate input assembly 'Interop.WMEncoderLib.dll' or one of its dependencies.

Then I tried :

C:\Program Files (x86)\Microsoft Visual Studio 11.0>regasm C:\WMSDK\WMEncSDK9\samples\C#\remadmin\WMEWebSvc\bin\Iterop.WMEncoderLib.dll

Yielded:

Same error.

Can someone please tell me what I'm doing wrong and how to solve this issue?