ASP.NET Website Administration tool "An error was encountered"

Hello, I have googled the similar problem that many people are facing but I still can't solve mine.

I'm trying to visit the ASP.NET Web Site Administration Tool at http://localhost:49274/asp.netwebadminfiles

The page shows me the error "An error was encountered. Please return to the previous page and try again."

Some says it has to do with web.config file, I'm new to ASP.NET, here is my web.config file


<?xml version="1.0" encoding="utf-8"?>
<!--
For more information on how to configure your ASP.NET application, please visit
http://go.microsoft.com/fwlink/?LinkId=152368
-->
<configuration>
<system.web>
<compilation debug="true" targ ...