Netbeans - setting for virtual host

I am using Netbeans 8.0. I had to set up a virtual host on my Apache to get

http://mysite.dev/index.php

      

        
        
        
      

    

instead

http://localhost/mysite/frontend/web/index.php

      

        
        
        
      

    

I was trying to set up Run Configuration in Netbeans (for xdebug target) and it seems to be impossible. When I installed Project URL

in:

http://mysite.dev

      

        
        
        
      

    

and Index File

just before index.php

the warning appears

Index File must be a valid relative URL

      

        
        
        
      

    

Warnings prevent debugging. I don't know how to solve it.

EDIT (for @akshayb):

<VirtualHost *:80>  
DocumentRoot "C:\wamp\www\mysite\frontend\web"
ServerName mysite.dev
</VirtualHost>

      

        
        
        
      

    

I don't think this is important. Netbeans doesn't even start a debug session. It just opens a window Run Configuration

asking me to change the field Index File

as per the warning.