Error: You can not duplicate mimeMap collection item with unique key attribute in ASP.Net

Thanks for your reply Andrea, I am getting following message

HTTP Error 500.19 - Internal Server Error The requested page can not be accessed because the related configuration data for the page is invalid. Detailed error information: Module : Custom Error Module Message : Send Response Handler : StaticFile error code : 0x800700b7 Configuration : You can not duplicate mimeMap collection item with unique key attribute 'fileExtension' set to '.ogg' configuration : \\? \ web.config Requested URL : http://SiteURL/Styles/Site2.css Physical path : C: \ \ Styles \ Site2.css login Method : Anonymous Logged in user : Anonymous

Configuration Source:     6: <staticContent>     7: <mimeMap fileExtension = ".ogg" mimeType = "audio / ogg" />     8: </ staticContent> More information: This error occurs when you are reading the configuration file for the web server or web application. The event log may contain more information about the cause of the error.

Hi abhi619,

Add below code in your web.config file

<system.webServer>
<staticContent>
    <remove fileExtension=".ogg" />
    <mimeMap fileExtension = ".ogg" mimeType = "audio / ogg" />
</staticContent>
</system.webServer>

It worked. Thanks AnandM