I recently ran into the error mentioned in the title:

Could not find schema information for the element 'http://schemas.microsoft.com/.NetConfiguration/v2.0:configuration'.

I couldn't start my application debugging anymore, and it got me stumped.

The solution is rather simple, yet not very obvious.

Open up your web.config file and look for:

<configuration xmlns="http://schemas.microsoft.com/

.NetConfiguration/v2.0"> 

 

Replace: 

 

<configuration xmlns="http://schemas.microsoft.com/

.NetConfiguration/v2.0"> 

with:

 

<configuration>

 

and add the xml directive to the top of your web.config like this:

<?xml version="1.0"?>

 

So it now should look something like this:

<?xml version="1.0"?>

 

<configuration>

You can now start debugging again and probably your intellisense is back!