get this error when i open doc file in browser

Server Error in '/' Application.

pastinghttp://biomantic.com/ViewDocument.aspx?name=Last%20testing%20for%20airseach.docx&url=C:\Users\bbharat\Documents\Downloads\DevOpsSourceCode\Newfolder\AIRSearchEngine\Data\Last%20testing%20for%20airseach.docx

Retrieving the COM class factory for component with CLSID {000209FF-0000-0000-C000-000000000046} failed due to the following error: 80040154 Class not registered (Exception from HRESULT: 0x80040154

(REGDB_E_CLASSNOTREG)).

 

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

 

Exception Details: System.Runtime.InteropServices.COMException: Retrieving the COM class factory for component with CLSID {000209FF-0000-0000-C000-000000000046} failed due to the following error: 80040154 Class not registered (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG)).

 

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

 

Stack Trace:

[COMException (0x80040154): Retrieving the COM class factory for component with CLSID {000209FF-0000-0000-C000-000000000046} failed due to the following error: 80040154 Class not registered (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG)).] System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck) +0 System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) +122 System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) +239 System.Activator.CreateInstance(Type type, Boolean nonPublic) +85 System.Activator.CreateInstance(Type type) +12 TokenService.GetFileContain(String SelectedFile) in C:\Users\bbharat\Documents\Downloads\DevOpsSourceCode\Newfolder\AIRSearchEngine\App_Code\TokenService.cs:98 AIRSearchEngine.WebForm1.Page_Load(Object sender, EventArgs e) in C:\Users\bbharat\Documents\Downloads\DevOpsSourceCode\Newfolder\AIRSearchEngine\ViewDocument.aspx.cs:16 System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +52 System.Web.UI.Control.OnLoad(EventArgs e) +97 System.Web.UI.Control.LoadRecursive() +61 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +693