The content index is not fully loaded.
To resolve this issue execute the following steps:
Look in the Application event log for Jet Database related events. The Application event log can be viewed through the Event Viewer snap-in which can be found in the Computer Management console. The following task will start the Computer Management console:
Start Computer Management Console
Address any issues in the event log that are responsible for this failure.
Once done, restart the SharePointPSSearch service. The service can be stopped and restarted using the following tasks:
Stop Search Service
Start Search Service
For information about the SharePointPSSearch service, see the Microsoft Office SharePoint Portal Server 2003 Administrator’s Guide.