"Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached."

namespace My_Project
{
    public abstract class global
    {





            public static SqlConnection conn()
            {

                SqlConnection cn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename='D:\My_Project\My_Project\DATABASE\Soneri_Bank_loan_system.mdf';Integrated Security=True;Connect Timeout=0; Max Pool Size = 100; User Instance=True");

                try
                {
                    cn.Open();
                }
                catch (Exception e1)
                {
                    MessageBox.Show(e1.Message);
                }
                return cn;
            }
        }