I need to validate a xml document against a xml schema. The xml document looks like <call type="Call" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="https://host/schema/someschema_in.xsd"> <header type="Header"/> <module>order</module> <operation>DoDebit</operation> </call> It must have worked via HTTPS. But the parser reports: Failed to read schema document 'https://host/schema/someschema_in.xsd' Please answer.