The provider did not return a ProviderManifestToken string
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I'm trying to teach myself .Net MVC 3, and am following this tutorial: http://www.asp.net/mvc/tutorials/getting-started-with-aspnet-mvc3/cs/intro-to-aspnet-mvc-3 and have reached the step where you create the controller for the Model you created earlier (http://www.asp.net/mvc/tutorials/getting-started-with-aspnet-mvc3/cs/accessing-your-model's-data-from-a-controller).

When I try to create the controller, I get the "The provider did not return a ProviderManifestToken string" error. A bit of googling leads me to believe this is due to an error with my connection string.

The thing is I'm not running SQL Server locally, so I can't copy the example connectionString. Here's what I've got now:  

    connectionString="Data Source=1.2.3.4\MSSQLSERVER;Initial Catalog=myDBname;Integrated Security=False;User ID=myUsername;Password=myPassword"

I've tried using SSMS to log on to the database using the username and password, and it works, so the problem is not with the user itself.

Any ideas?