Here are some Microsoft support documents for specific OneCare problems.
- Windows Live OneCare Firewall Repair Tool – The OneCare firewall reports that it cannot install a required upgrade or cannot turn on the firewall.
- “Antivirus service could not start” – a problem in the Windows startup file (Boot.ini) that can prevent the Windows Live OneCare Antivirus service from starting.
- Updating Windows Live Onecare Application or Virus and Spyware Protection Fails
- Windows Live OneCare indicates that signatures for the antivirus program are out of date, and the icon on the taskbar is red
Here is a list of general and specific troubleshooting tips.
If you need technical support from Microsoft, this page describes the flow that leads to e-mail or phone support. Basically, you’ll go to this page, click on “Get more help” in the lower right, then click on “Get support.”
The OneCare forums are a good source of information and feature a very dedicated guy named Stephen Boots who tries hard to solve problems and make people feel better.