If you see an error stating that "Microsoft Office support for the .NET Framework 4.0 is not installed," your installation of Microsoft Office may be corrupt. Follow these steps to repair it:
- Open the Control Panel.
- Under Programs, select Uninstall a program.
- Right-click on the Microsoft Office listing and select Change.
- Choose a Repair option and follow the steps in the wizard.
- When the repair is finished, install the add-in.