asp.net mvc - Error in webconfig file -

I am new to MVC 4. I am working on browsing the Internet on which I am working and I Model for my application. I have created one and when I try to add a controller, I get an error message.

  'Unable to retrieve metadata for practice .Models. Customer '. Valid for' attachdbfilename '  
  Model :  
  public class customer {public entry id {received Do; Set; } Public string name {get; Set; } Receive the public int amount; Set;}} Public class customer DBCettext: DBcinTex {Public DBset & lt; Customers & gt; Customer {Received; Set; }}   
  Connection String :  
  & lt; Connection best & gt; & Lt; Add name = "DefaultConnection" connectionString = "data source =. \ SQLEXPRESS; initial catalog = aspnet-practice-20130320183458; integrated security = SSPI" provider name = "System.Data.SqlClient" /> & Lt; Add name = "CustomerDBContext" connectionString = "data source = (locali) \\ v11.0; attachment debufflename = | datadirectory | \ customer.mdf; integrated security = sspi" provider name = "system.data.sql client" / " Gt;   
  
 I think there is some problem with the connection string but do not know where it is. Please help me solve this problem..Thank you in Thanksgiving   
 
 
 I think your Make virtual virtual  
  Public Virtual Ent ID {get; Set; } Public Virtual String {get} Set; } Public Virtual Space {get; Set;}