After a Windows Vista-based computer uses a Windows HTTP Services (WinHTTP) component, such as the ServerXmlHttp object, to send a POST request to a Web server, the same request is resent to the server.

This behavior occurs if the keep-alive connection that is used for the first POST request is reset by the Web server.

Note: To verify this behavior, you can use a network sniffer, or you can check the WinHTTP log.