Steps 1: Install the trial version of Office Word from the location below if you do not have an existing copy of Office Word: ...

Steps 1: Install the trial version of Office Word from the location below if you do not have an existing copy of Office Word: http://www.microsoft.com/office/trial/default.mspx 
Steps 2: Select Custom Install during Office setup
Step 3: Select all the Office application you would like to install including Word. Select the "Choose advanced customizations of applications" checkbox which is on the same wizard screen.
Step 4: On the "Advanced Customization" screen expand the Microsoft Office Word tree
Step 5: Select the ".NET Programmability Support" option and choose to "Run all from my computer"
Step 6: Complete Microsoft Office Word Setup
Step 7: Install the Microsoft Visual Studio Tools for the Microsoft Office System: 
http://go.microsoft.com/fwlink/?LinkId=53267