    <!-- Web.Config Configuration File -->

    <configuration>
        <system.web>
            <customErrors mode="Off"/>
        </system.web>
    </configuration>

Notes: The current error page you are seeing can be replaced by a custom error page by modifying the "defaultRedirect" attribute of the application's <customErrors> configuration tag to point to a custom error page URL.

    <!-- Web.Config Configuration File -->

    <configuration>
        <system.web>
            <customErrors mode="RemoteOnly" defaultRedirect="mycustompage.htm"/>
        </system.web>
    </configuration>