I'm not sure if you are having a problem, but you mention in the subject line that you had to reinstall OneCare.
After the reinstall, you will need to activate with your existing subscription LiveID.
If you need help, please contact support.
How to reach support (FAQ) - http://forums.microsoft.com/WindowsOneCare/ShowPost.aspx?PostID=2421771&SiteID=2
-steve