C#

if (!String.IsNullOrEmpty(CustodianEAddress.Text))
{
    for (AddressLength1 = 0; AddressLength1 < Length; AddressLength1++)
    {
        List<string> list1 = new List<string>();
        using (StreamReader reader = new StreamReader(FileLocation))
        {
            string line1;
            //max 500
            string[] LineArray1 = new string[500];

            while ((line1 = reader.ReadLine()) != null)
            {
                list1.Add(line1); // Add to list.

                if (line1.IndexOf(cust1[AddressLength1].ToString()) != -1)
                {
                    count1++;
                    LineArray1[count1] = line1;
                }
            }

            reader.Close();
            using (System.IO.StreamWriter filed = 
               new System.IO.StreamWriter(FileLocation, true))
            {
                filed.WriteLine("");
                filed.WriteLine("The email address " + 
             cust1[AddressLength1].ToString() + " was found " + count1 +
             " times within the recipient's inbox");
            }

            string count1a;
            count1a = count1.ToString();
        }
    }
}
else
{
    MessageBox.Show("Please Enter an Email Address");
}