The Aspnet_regbrowsers.exe is registration tool which parses
and compiles all system-wide browser definitions that are contained browser
files into an assembly and installs the assembly into Global Assembly Cache.
In ASP.NET 1.1 the browser information of all the supported browsers was contained in a section called <browserCaps>, where the meta data is
in the form XML entries for various browsers.
In ASP.NET 2.0 a new file called .Browser maintains the data
of all the browsers in the form xml entries.
We can find the .Browser files of various browsers in the
\Microsoft.NET\Framework\version\CONFIG\Browsers on your
These files are complied into an assembly called
Asp.BrowserCapsFactory.dll using the Aspnet_RegBrowsers.exe tool.
This allows the server to access the new browser information
immediately so you do not have to shut down any of your applications to pick up
the information. An application can access browser capabilities through the
Browser property of the current HttpRequest.
These are the options provided by the Aspnet_Regbrowser.exe.
Displays all the available options provided by the tool.
Creates the assembly and deploys in the GAC.
Eg: Aspnet_Regbrowsers.exe –I
Uninstalls the assembly from the GAC.
Eg : Aspnet_Regbrowsers.exe -u
Do not change the predefined browser definition files that
come with ASP.NET because service packs might update those files and overwrite
Application-specific browser definition files can be placed
in the application's App_Browsers directory. In both locations, browser
definition files must have a .BROWSER file name extension. Using the ASP.NET
Browser Registration tool has no effect on application-specific browser
definition files stored in an application's App_Browsers directory.
Using the <browserCaps> element in the Web.config file
to define browsers is deprecated in the .NET Framework version 2.0, but is
still supported. The data in this element is merged with the information from
the browser definition files.