Problem refreshing tables in the LINQ to SQL designer

[Table("dbo.my_table")]
public class MyTable
{
[Column("id", AutoSync = AutoSync.OnInsert, IsDbGenerated = true, IsPrimaryKey = true)]
public Int32 Id { get; set; }

[Column("name", DbType="NVarChar(50) NOT NULL")]
public String Name { get; set; }
}