Microsoft.Office.Interop.Word.Application COM Error

I am creating a web application; on click a button will open a word document using Microsoft.Office.Interop.Word.Application; it's working well in my PC, but in server I am getting COM exception.

Error is like this:

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)).