The Microsoft Single Sign-On (SSOSrv) service did not start.
Do the following:
Try restarting the service.
If you have restarted the computer, check that the startup type for the service is not set to Manual or Disabled.
Ensure that you are running a supported topology.
Ensure that you are connected to all databases.
For information about configuring single sign-on, see the Microsoft Office SharePoint Portal Server 2003 Administrator’s Guide.