With the disc inserted in your CD/DVD drive, open My Computer from the stsrt menu, right click the icon for the CD/DVD drive, select "Explore" from the context menu, look for a file called "Setup.exe" and double click it. This will launch the One Care setup program.
There is an easier way to install One Care though. Go to the One Care website - http://onecare.live.com/standard/en-us/default.htm and download the 90 day trial.
To activate One Care, after installation open One Care and select "Subscribe" or "Activate". Follow the prompts,create a Live ID or use an existing one, when you get to the payment screen select ""Pre-Paid PIN or Token" as the payment method, enter the 25 digit product key that came with the CD and your subscription should activate. After subscribing write down your Live ID and password. If you ever need to reinstall One Care or install on another computer you will need your Live ID and password.
