Cannot install Powershell Snap-in

As the error suggests, it should already be installed as part of your Windows 7 operating system.

You may need to execute (or add to your profile) the following statement to load the module:

import-module WebAdministration

I think it may already be part of Window 7. In programs and features | turn Windows features on or off | Web Management Tools | IIS Management Scripts and Tools ??

System Requirements Supported Operating Systems: Windows Server 2008; Windows Vista Windows Vista Service Pack 1 and later. Windows Server 2008 and later. Windows Powershell 1.0 or 2.0.
Instructions You will need to run the installation package as an administrator. This can be accomplished by one of the following methods: Logging in to your server using the actual account named "Administrator". Logging on using an account with administrator privileges and opening a command-prompt by right-clicking the Command Prompt menu item that is located in the Accessories menu for Windows programs and selecting "Run as administrator", then typing the command listed below: msiexec /I iis7psprov_x64.msi If you already have a Beta or RC release of the IIS Powershell Snap-in installed the installation package will ask you to uninstall this version first.