Entity Framework not creating Tables - sql-server

Question

I really have no luck with the EF every time. This time it looks like this:
First time i created a context i had an error like:
Invalid object name 'dbo.TableName1'
After this setting the Database Initializer to CreateDatabaseIfNotExists T it did the trick.
Next i created a different context, which was changed at some point of the development. So this time i keep getting this error:
The model backing the 'NewContext' context has changed since the database was created.
I found a solution to set the Database Initializer to null, but after this i keep getting the first error:
Invalid object name 'dbo.TableName2'
I also tried to set the the initializer to DropCreateDatabaseIfModelChanges and DropCreateDatabaseAlways, and these settings throw the exception:
Cannot drop database "DatbaseName" because it is currently in use
I think I already tried everything i found on the Web (there are many topics of this kind) but none helped me with it.
Dropping the Database didn't help, nor changing from Local File Database to SQL Server 2014 Exspress. The same exception is thrown. Any ideas?
Edit1:
Working context:
public class ProfilesContext : DbContext
{
public ProfilesContext() : base("DefaultConnection")
{
}
public DbSet<Profile> Profiles { get; set; }
public DbSet<PrevilegedContact> PrevilegedContacts { get; set; }
}
Failing context:
public class PlacesContext : DbContext
{
public PlacesContext()
: base("DefaultConnection")
{
}
public DbSet<Place> Places { get; set; }
public DbSet<Price> Prices { get; set; }
public DbSet<Photo> Photos { get; set; }
public DbSet<Comment> Comments { get; set; }
}

Answer 1

For what you are doing, it seems you have 2 options for your initializer. There is Migrations and there is DropCreateDatabaseIfModelChanges.
Migrations will give control over updating the database tables when your models change and allow you to preserve data. You can configure it to allow data loss or not. Very useful during development time if you already have test data in there.
DropCreateDatabaseIfModelChanges will simply drop the database each time you make model changes and recreate it with the new schemas.
You are getting the error message
Cannot drop database "DatbaseName" because it is currently in use
because you have more than likely browsed the table in your server explorer and have an open connection to the database. You can close the connection using the right click context menu in server explorer.
If you want a video overview on Migrations there is a free video by Scott Allen & Pluralsight. This is MVC4 but the Entity Framework section does cover Initalizers. If you want an updated one for MVC5 to include multiple Contexts etc, it does exist but you would need to take the Pluralsight free trial to get access to it.

Answer 2

I agree with James. Good point about checking Server Explorer. Right-click the database and choose Close Connection or at least check that there is a red X indicating the connection is closed. The link below is a great tutorial on the basics with Code First Migrations. The link is directly to the page within the tutorial that talks about making model changes and how to make EF happy again! http://www.asp.net/mvc/tutorials/mvc-5/introduction/adding-a-new-field. I prefer using Migrations. You would use the Package Manager Console and 1) Enable Migrations, 2) Add a migration, 3) Update the database. If in development, use LocalDb if possible, and use the Seed method in the Configuration class to prepopulate the database.