Is this a new install or an update?
See if these links help:
Firewall repair tool - http://forums.microsoft.com/WindowsOneCare/ShowPost.aspx?PostID=2468376&SiteID=2
OneCare won't start - http://forums.microsoft.com/WindowsOneCare/ShowPost.aspx?PostID=2523777&SiteID=2
Virus and Spyware repair tool - http://forums.microsoft.com/WindowsOneCare/ShowPost.aspx?PostID=2667445&SiteID=2
If not, please contact support -
How to reach support (FAQ) - http://forums.microsoft.com/WindowsOneCare/ShowPost.aspx?PostID=2421771&SiteID=2