I got this error on my test server, and by following http://support.microsoft.com/kb/938219 to remove the proxy settings that are configured in Internet Explorer on the server that hosts the Shared Service Provider (SSP), and then restart the Office SharePoint Server Search service. But the error is still there. Finally, I found someone add proxy serer in Crawling -> Proxy and timeouts. By click the “Do not connect by using a proxy server”, the crawling back to work.
This is a common issue, if you are Fam Admin and when you click the “User profile and propertirs” in Shared Service, you got access denied.
You need to click Personalisation Services Permissions, and add yourself to the permissions listed in there. By default it will add only the account you used to set up the SSP.