As per Microsoft: "Windows Management Instrumentation (WMI) automatically processes all performance counters to create Common Information Model (CIM) classes that represent each performance counter. The performance counters can be viewed in the perfmon.exe utility. When a specific performance library cannot supply the information about which performance counters it publishes, the counters are not available through WMI. In many cases, this is because the service publishing the performance counter is not running or because there is a bug in the service's performance library". See MSW2KDB
for more details.
In my case, this warning appeared after installing the Microsoft.NET Framework SP1 and rebooting ( Server is Windows 2000 Server, SP2, running Terminal Services and Citrix MetaFrame 1.8.)
From a newgroup post: "This error is usually associated with another application grabbing port 80. If something else is using port 80, IIS will be unable to start the default website. You can try changing the port to 81 on the Home Directory tab in the Properties of the Default Website and see if it then starts. If it does start up IIS is working but something else is using port 80."
Caused by the presence of a http proxy running on the server giving these events. Disabling the proxy fixes the problem. Suspect proxy and IIS are competing for port 80 and perhaps other resources.