Server Application Error

The server has encountered an error while loading an application during the
processing of your request. Please refer to the event log for more detail
information. Please contact the server administrator for assistance.

There's the message.

I looked in the event log, it said it couldn't find a file, but I can't remember
what. Seeming I'm on a different computer, I'll have to post that in the
morning.

I uninstalled and reinstalled IIS. It's an HP Media Center.

Here's the error:

The server failed to load application '/LM/W3SVC/1/ROOT'.  The error was 'Class
not registered
'. 
For additional information specific to this message please visit the Microsoft
Online Support site located at: http://www.microsoft.com/contentredirect.asp.

For more information, see Help and Support Center at
http://go.microsoft.com/fwlink/events.asp.