[oXygen-user] Failed to read schema document

Hi, I'm trying to set up eXist to validate records with schema. But I keep getting error message when I tried to save a record in eXist. Cannot save the file. org.xml.sax.SAXParseException: schema_reference.4: Failed to read schema document 'file:/export/home/library/eXist/webapp//WEB-INF/entities/works.xsd', because 1) could not find the document; 2) the document could not be read; 3) the root element of the document is not <xsd:schema>. Does anyone know what might cause this error message? The schema's root is <xsd:schema> I am sure about that. Thanks. Jenny