I created an MVC3 Internet application and changed the default connection string to work with
.\SQLSERVER instead of the default .\SQLEXPRESS and get following error :
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Shared Memory Provider, error: 40 – Could not open a connection to SQL Server)
I tried creating an empty MVC3 application as well, which has no connection string by default and added mine with the same result.
The SQLSERVER instance is running and I can connect to it from management studio using windows authentication. Any connection string that I use gives same error, I cannot figure it out:
<connectionStrings>
<remove name="LocalSqlServer" />
<add name="LocalSqlServer" connectionString="data source=.\SQLSERVER;" providerName="System.Data.SqlClient" />
</connectionStrings>
Perhaps I had to mention that I was using EF with code first approach, but the problems was due to the name of the connection string which should be the same name as your Context which you derive from DbContext, e.g.:
as well make sure you remove the default machine.config connection string which is for .\SQLEXPRESS