I've not encountered that issue being reported before, so I can only guess at a possible solution.
You can contact support for help, if you want:
How to reach support (FAQ) - http://social.microsoft.com/Forums/en-US/onecareinstallandactivate/thread/30400b52-7f26-4ba0-bc18-17e305329d90
What I'd try first, though, would be to reset the database:
http://www.microsoft.com/downloads/details.aspx?FamilyID=4bc2594b-95ab-4235-b5b8-41656b38480f&DisplayLang=en
Another possibility, though not likely, is that .Net Framework is broken. That usually manifests itself by a complete failure of OneCare to open, though it remains running. I don't have links for the latest 3.5 roll-up of .Net Framework, but the steps below take care of 2.0:
To repair .Net Framework 2.0 on XP:
Open Control Panel
Select Add or Remove Programs
Locate Microsoft .Net Framework 2.0
Select the entry and when the installer launches, select Repair.
Reboot when it completes.
Alternatively, see this KB article:
http://support.microsoft.com/kb/306160
To remove a corrupt .Net Framework install, use this tool:
http://astebner.sts.winisp.net/Tools/dotnetfx_cleanup_tool.zip
The download of .Net Framework 2.0 can be found here:
http://www.microsoft.com/downloads/details.aspx?familyid=0856eacb-4362-4b0d-8edd-aab15c5e04f5&displaylang=en
To repair .Net Framework 2.0 and 3.0 on Vista, see this blog entry:
http://blogs.msdn.com/astebner/archive/2007/03/26/how-to-repair-the-net-framework-2-0-and-3-0-on-windows-vista.aspx
And, it may be worth reinstalling OneCare even before trying the .Net Framework repair if the database reset tool doesn't work.
-steve
Microsoft MVP Windows Live / Windows Live OneCare & Live Mesh Forum Moderator
