The IIS6 Management Compatibility components need to be installed on IIS8 in order to install and run Practical Password Reset.

In Server 2012, go to Add Roles and Features. If you have not installed the Web Server Role, be sure to select that from the Server Roles section. When you get to the Role Services page for the Web Server Role, you will have the option to select IIS 6 Management Compatibility.

Role Services screen