After clicking on Crawling, nothing happens for a couple of minutes and then I get the error message below. I also get an e-mail indicating that 478 pages were indexed.
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator, [external links are visible to admins only] and inform them of the time the error occurred, and anything you might have done that may have caused the error.
More information about this error may be available in the server error log.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
Apache/2.2.10 (Unix) mod_ssl/2.2.10 OpenSSL/0.9.7a mod_auth_passthrough/2.1 mod_bwlimited/1.4 FrontPage/18.104.22.16835 Server at [external links are visible to admins only] Port 80