Mails not retrieving from Gmail

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WinForms

C#3.5

SQL-Server-2008R2

I was using this Limilabs Mail.dll and after deleting the mails retrieved from it first time through this code Now I am receiving no mails.
Below is the code:

string conn = @"Data source=(local);Initial Catalog=fyp;Integrated Security=true";
SqlConnection con = new SqlConnection(conn);
string add, name;
byte[] buffer;
using (Pop3 pop3 = new Pop3())
{
    pop3.Connect("pop.gmail.com", 995, true);  // or ConnectSSL for SSL
    pop3.Login("username", "password");

    // Receive all messages and display the subject
    MailBuilder builder = new MailBuilder();
    foreach (string uid in pop3.GetAll())
    {
        IMail email = builder.CreateFromEml(
          pop3.GetMessageByUID(uid));


        foreach (MailBox m in email.From)
        {
            add = m.Address;
            name = m.Name;


            string date = (email.Date).ToString();
            string sub = (email.Subject);
            string text = (email.Text);

            foreach (MimeData mime in email.Attachments)
            {
                mime.Save(@"d:\" + mime.SafeFileName);
                buffer = mime.Data;


                string qry = "insert into retmail_2 values (@sub,@text,@date)";
                SqlCommand cmd = new SqlCommand(qry, con);
                cmd.Parameters.AddWithValue("@sub", sub);
                cmd.Parameters.AddWithValue("@text", text);
                cmd.Parameters.AddWithValue("@from", add);
                cmd.Parameters.AddWithValue("@name", name);
                cmd.Parameters.AddWithValue("@date", date);
                cmd.Parameters.AddWithValue("@attch", buffer);
                con.Open();
                int g = cmd.ExecuteNonQuery();

                con.Close();

            }
            pop3.Close();
        }
    }

Now it is retrieving no mails so guys can you tell me some permanent solution other than this because it is retrieving no mails now.Thing is all the mails that r retrieved they are stored in a datagridview given in the windows form. Now on row cell click event it was shows mails also when it retrieves mails it inserts them into a table made in sqlserver 2008 its in which there is an autogenerated integer type uid. Now on debugging it is showing uid -1 in gridview and nothing is retrieved in the database.
i thought that the mails are not retrieving from the mail server.Thats why this is happening. I dont know other way to retrieve mails from a server.
Help me PLZ.