When running Windows Update in Windows Server 2008, Windows Update may fail with the error code 80070057. This is caused by the winHTTP Web Proxy Auto Discovery Service. WinHTTP implements the client HTTP stack and provides developers with a Win32 API and COM Automation component for sending HTTP requests and receiving responses. In addition, WinHTTP provides support for auto-discovering a proxy configuration via its implementation of the Web Proxy Auto-Discovery (WPAD) protocol.
To resolve the problem, stop this service and run the Windows Update again. To stop the service,
1. Click Start – Search for Services.msc and press enter.
2. In the right-pane, scroll down to the “winHTTP Web Proxy Auto Discovery Service“. Right-click and select “stop”.
3. Now, start Windows update and should run without errors this time.