Using her computer download the One Care trial -
http://onecare.live.com/standard/en-us/3/default.htmTo activate,open One Care, select "Subscribe". To add the computer to your account, when asked for a Live ID enter the Live ID and password associated with your One Care subscription and One Care will activate.
If you have a One Care CD that has never been activated select "Subscribe" and follow the prompts. When you reach "method of payment" select "Pre-paid PIN or Token" and enter the product key from the CD.
Jim