What is Machine.config? 

Machine configuration file: The machine. config file have settings that apply to the entire computer. This file is located in the %runtime install path%Config directory. There is only single machine. config file on a computer. The Machine.Config file found in the "CONFIG" subfolder of your .NET Framework install directory (c:WINNTMicrosoft.NETFramework{Version Number}CONFIG on

Windows 2000 installations). The machine.config, which can be found in the directory $WINDIR$Microsoft.NETFrameworkv1.0.3705CONFIG, is an XML-formatted configuration file that specifies configuration options for the machine. These files have, among many other XML elements, a browserCaps element. Inside this element are a number of other elements that specify parse rules for the variety of User-Agents, and what properties every of these parsings supports.