Sending Email VB.net Exception

Question

this is my code it was running without errors but suddenly an exception appears The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required.

Dim smtpserver As New SmtpClient()
    Dim mail As New MailMessage()
    smtpserver.Credentials = New Net.NetworkCredential("[email protected]", "mypass")
    smtpserver.Host = "smtp.gmail.com"
    smtpserver.Port = "587"
    mail = New MailMessage
    mail.From = New MailAddress("[email protected]")
    mail.To.Add(Form2.TextBox1.Text)
    mail.Subject = "EagleEyes"
    mail.Body = "EagleEyes has detected a movement!"
    If emailphoto Then
        Dim attach As New Attachment("D:\hi" & sm & ".jpg")
        mail.Attachments.Add(attach)
    End If
    smtpserver.EnableSsl = True

    smtpserver.UseDefaultCredentials = False

    '   Try1
    smtpserver.Send(mail)
    'Catch ex As SmtpException
    'MsgBox("Error Connection!" & ex.Message)

    'End Try
    sm += 1

Answer 1

Don't use "" by the port.

Please try this for the port:

smtpserver.Port = 587