Entity Framework throws exception - Invalid object name 'dbo.BaseCs'

Exception Details: System.Data.SqlClient.SqlException: Invalid object name 'dbo.BaseCs'

This error means that EF is translating your LINQ into a sql statement that uses an object (most likely a table) named dbo.BaseCs, which does not exist in the database.

Check your database and verify whether that table exists, or that you should be using a different table name. Also, if you could post a link to the tutorial you are following, it would help to follow along with what you are doing.

It is most likely a mismatch between the model class name and the table name as mentioned by 'adrift'. Make these the same or use the example below for when you want to keep the model class name different from the table name (that I did for OAuthMembership). Note that the model class name is OAuthMembership whereas the table name is webpages_OAuthMembership.

Either provide a table attribute to the Model:

[Table("webpages_OAuthMembership")]
public class OAuthMembership

OR provide the mapping by overriding DBContext OnModelCreating:

class webpages_OAuthMembershipEntities : DbContext
{
    protected override void OnModelCreating( DbModelBuilder modelBuilder )
    {
        var config = modelBuilder.Entity<OAuthMembership>();
        config.ToTable( "webpages_OAuthMembership" );            
    }
    public DbSet<OAuthMembership> OAuthMemberships { get; set; }        
}