Cannot access individual products

In Marketpress

When I click on a link for a particular product I get

"Not Found
Apologies, but the page you requested could not be found. Perhaps searching will help."

Server error log is reporting this

"[Wed Sep 29 19:56:23 2010] [notice] cannot use a full URL in a 401 ErrorDocument directive --- ignoring!"

I already went to the store settings/presentation page and resaved and it did not work.

I can provide a snapshot if needed. The client don't want me showing their site just yet.