Use this dialog box to add to or modify the mapping between a file name extension and the program or interpreter that processes those files. The Executable is the name of the .exe or .dll that you want to run. The executable file must be located on your Web server's local hard disk. The Extension is the file name extension associated with your application. If you do not want all HTTP verbs to be passed to your applications through these mappings, then you can set restrictions appropriately. For example, by default, the file Asp.dll processes requests using the HTTP verbs GET, HEAD, and POST. (TRACE requests are handled by IIS.) To enable all verbs, select the All Verbs radio button. Separate verb or method names with a comma (,).


Type the name of the executable file (.exe or .dll). The executable file must be located on your Web server's local hard disk.


Click to locate your Web server's local hard disk for the executable file (.exe or .dll).


Type the file name extension associated with your application.


This allows options to restrict the number of HTTP verbs that can be associated with each application extension.

You can select one of two options:

Script engine

Select when you want the application to run in a directory without execute permissions. This setting is intended primarily for script-based applications, such as ASP and IDC, that are mapped to an interpreter. To run a script-mapped application, you must select either Script only or Scripts and Executables from the Execute permissions list box on the Directory tab for the directory in which the application is located.

Verify that file exists

Select to instruct the Web server to verify the existence of the requested script file and to ensure that the requesting user has access permission for that script file. If the script does not exist or the user does not have permission, the appropriate warning message is returned to the browser and the script engine is not invoked. This option can be useful for scripts mapped to non-CGI executables, such as the Perl interpreter, that do not send a CGI response if the script is not accessible. Because the script must be opened twice, once by the server and once by the script engine, enabling this option can impact performance.

Related Topics

To learn more about configuring applications, see the IIS 6.0 online documentation on the Microsoft Windows Server TechCenter.