Hosting in IIS (503 Service Unavailable)

Question

I am trying to host my WCF service in IIS 7.5, but everytime i run the website i get a page stating

Service Unavailable

HTTP Error 503. The service is unavailable.

I noticed that whenever I started the website the ASP.net v4.0 stopped automatically. I checked the eventviewer and this seems to be the error

The worker process for application pool 'ASP.NET v4.0' encountered an error 'Configuration file is not well-formed XML ' trying to read configuration data from file '\\?\\C:\\Windows\\Microsoft.NET\\Framework64\\v4.0.30319\\CONFIG\\web.config', line number '0'. The data field contains the error code.

I tried searching for solutions around the internet but none of them have been helpful so far.

1. I tried changing the identity of ASP.net v4.0 in IIS to LocalSystem and it didn't work

2. After that i tried setting up a "Custom account" by setting the username as my computer username and adding passwords but i got "The specified password is invalid, type a new password" even though i don't have any passwords for my account

3.The final thing i tried was to add IIS_IUSRS and IUSR to the security of the Web.config but still it didn't work

This is my Web.config

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <system.serviceModel>
    <behaviors>
      <serviceBehaviors>
        <behavior name="mexBehavior">
          <serviceMetadata httpGetEnabled="true" />
        </behavior>
      </serviceBehaviors>
    </behaviors>
    <services>
      <service behaviorConfiguration="mexBehavior"
               name="HelloService1.HelloService1">
        <endpoint address="HelloService1" binding="basicHttpBinding"
            contract="HelloService1.IHelloService1" />
        <host>
          <baseAddresses>
            <add baseAddress="http://localhost:8080" />
          </baseAddresses>
        </host>
      </service>
    </services>
  </system.serviceModel>

</configuration>

Answer 1

Try a re-install of the .NET Framework 4.0. Go to this location

%windir%\Microsoft.NET\Framework64\v4.0.30319

Run this command

aspnet_regiis -i