مشکل هنگام فرستادن ایمیل به تعداد بالا

[peymannaji]

با سلام
من یک تیکه کد کوتاه نوشتم برای فرستادن ایمیل به تعداد بالا که چندتای اول رو که میفرسته بعد اروری که ضمیمه کردم پیش میاد ... لطفا راهنمایی فرمائید که چگونه این کد را بهینه کنم تا اون اروری که زمیمه کردم پیش نیاد ... و اصولا این مشکل از سمت بنده هست یا میل سرور ؟





Dim send As Integer = 0
Dim fail As Integer = 0

Dim FROM As New MailAddress("tools@qesign.net")
Dim RECIVER As MailAddress
Dim MY_EMAIL As MailMessage

Dim SmtpMail As New SmtpClient
SmtpMail.Host = "mail server address"

Dim theCredential As New System.Net.NetworkCredential("username", "password")
SmtpMail.Credentials = theCredential

Dim emailaddress As String = Nothing
Dim connection As New SqlConnection("Data Source=.;Initial Catalog=EmailBank;Integrated Security=True")
Dim command As New SqlCommand("select * from EmailList", connection)
command.CommandType = CommandType.Text
Dim reader As SqlDataReader

connection.Open()
reader = command.ExecuteReader

For i As Integer = 0 To 1600

reader.Read()
emailaddress = reader(0).ToString
RECIVER = New MailAddress(emailaddress)
MY_EMAIL = New MailMessage(FROM, RECIVER)
MY_EMAIL.Subject = TextBox1.Text
MY_EMAIL.Body = TextBox2.Text
MY_EMAIL.IsBodyHtml = True
System.Threading.Thread.Sleep(5000)

Try
SmtpMail.Send(MY_EMAIL)
send += 1
Catch ex As Exception
fail += 1

End Try

Next

MessageBox.Show("fail=" & fail & " send=" & send)

[peymannaji]

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