Do you mean that you are unable to install because you can't setup your wireless connection for the laptop to the router? If so, check you router documentation on how to reset it to the factory defaults. Or, connect the laptop to the router with an ethernet cable to install OneCare.
Of, do you mean that you don't remember the LiveID and password for your subscription to OneCare? If so, open OneCare on the desktop and click Help/About to see the subscription ID - that's the LiveID. If you need to reset the LiveID password, you can do this at http://account.live.com
If you need help, you can reach out to support -
How to reach support - http://forums.microsoft.com/WindowsOneCare/ShowPost.aspx?PostID=2421771&SiteID=2
If it fails to validate your subscription, select the option that you are using a trial or beta copy and you can proceed to email support without validation once you've signed in.
-steve
