Is the OneCare firewall reporting that it is off? Is the Windows Firewall on or off? The Windows Firewall needs to be off and then OneCare firewall on, from within OneCare.
If the Windows Firewall is off (status in Windows Security Center), and the OneCare firewall is off and won't turn on, try:
Firewall repair tool - http://social.microsoft.com/forums/en-US/onecarefirewall/thread/e67b1989-afd5-47e5-a393-3a551c7c7e60/
If that does not resolve it, please contact support.
How to reach support (FAQ) - http://social.microsoft.com/Forums/en-US/onecareinstallandactivate/thread/30400b52-7f26-4ba0-bc18-17e305329d90
-steve
~ Microsoft MVP Windows Live ~ Windows Live OneCare| Live Mesh|MS Security Essentials Forums Moderator ~