If you are experiencing problems installing EZdrummer or Superior Drummer 2.0 on Windows Vista or Windows 7 you should go to the Toontrack website http://www.toontrack.com, login with your username and password and download the latest version of your product.
When you click 'My Products' on the top right, a list of registered products will appear.
Click on the product which you want to download. Two red tabs will appear in the top left.
Select either PC or Mac. This will download the full latest version.
Download the product and install.