Windows HTTP Services


Microsoft Windows HTTP Services (WinHTTP) provides developers with an HTTP client application programming interface (API) to send requests through the HTTP protocol to other HTTP servers.

Where applicable

WinHTTP supports desktop client applications, Windows services, and Windows server-based applications.

For more information on how to use WinHTTP for applications built on the Microsoft .NET Framework, see the WinHttpHandler API

Developer audience

WinHTTP offers both a C/C++ application programming interface (API) and a Component Object Model (COM) automation component suitable for use in Active Server Pages (ASP) based applications.

A basic understanding of the HTTP protocol is important to use either interface.

Run-time requirements

WinHTTP 5.1 offers improvements over version 5.0. It is included in the operating system. For more information about new features, see What's New in WinHTTP 5.1 and What's New in Windows Server 2008 and Windows Vista.


The WinHTTP 5.0 download is no longer available. As of October 1, 2004, Microsoft removed the WinHTTP 5.0 SDK download from MSDN and terminated product support for version 5.0.


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