C:\Program Files\Microsoft Visual Studio 8\ReportViewer or
C:\Program Files\Microsoft Visual Studio 9.0\ReportViewer
C:\Program Files\Microsoft Visual Studio 9.0\ReportViewer
You can manually copy the following dll files into the application folder /bin directory. After copying the files into the application bin folder the web application will start responding successfully. And ASP.NET ReportViewer control will work on your web application.
Bytes!! :)