Windows Server - Error de Transporte en la conexión al servidor

Set objMessage = CreateObject("CDO.Message")

'Const SMTPSSL = True

'Monitoreo de error

On Error Resume Next

'==This section provides the configuration information for the remote SMTP server.

'==Normally you will only change the server name or IP.

objMessage.Configuration.Fields.Item _

("http://schemas.microsoft.com/cdo/configuration/sendusing") = 2

'Name or IP of Remote SMTP Server

objMessage.Configuration.Fields.Item _

("http://schemas.microsoft.com/cdo/configuration/smtpserver") =  "smtp.office365.com"

'Type of authentication, NONE, Basic (Base64 encoded), NTLM

objMessage.Configuration.Fields.Item _

("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate") = 1

'Your UserID on the SMTP server

objMessage.Configuration.Fields.Item _

("http://schemas.microsoft.com/cdo/configuration/sendusername") =  "prueba@dominio.com"

'Your password on the SMTP server

objMessage.Configuration.Fields.Item _

("http://schemas.microsoft.com/cdo/configuration/sendpassword") =  "Prueba1"

'Server port (typically 25)

objMessage.Configuration.Fields.Item _

("http://schemas.microsoft.com/cdo/configuration/smtpserverport") =  587

objMessage.Configuration.Fields.Item _

("http://schemas.microsoft.com/cdo/configuration/smtpusessl") = False

'SMTPSSL

'Connection Timeout in seconds (the maximum time CDO will try to establish a connection to the SMTP server)

objMessage.Configuration.Fields.Item _

("http://schemas.microsoft.com/cdo/configuration/smtpconnectiontimeout") = 60

objMessage.Configuration.Fields.Update

objMessage.Subject = "Correo prueba office365"

objMessage.From = "prueba@dominio.com"

objMessage.To = "juan@dominio.com"

objMessage.Bcc = ""

objMessage.TextBody = "correo prueba"

objMessage.Send

Dim mailMsg As New MailMessage

with mailMsg

	.Fields.Item("http://schemas.microsoft.com/cdo/configuration/smtpserverport")= "465"

	.Fields.Item("http://schemas.microsoft.com/cdo/configuration/smtsperver")= "smtp.gmail.com"

	.Fields.Item("http://schemas.microsoft.com/cdo/configuration/sendusing")= "2"

	.Fields.Item("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate")= "1"

	.Fields.Item("http://schemas.microsoft.com/cdo/configuration/smtpusessl")= "1"

	.Fields.Item("http://schemas.microsoft.com/cdo/configuration/sendusername")= "micorreo@gmail.com"

	.Fields.Item("http://schemas.microsoft.com/cdo/configuration/sendpassword")= "miclave"

	.From = "pedroinfante@gmail.com"

        .To = "joseperez@gmail.com"

	.Subject = "Correo de Prueba"

	.Body = "Prueba de correo"

End With

SmtpMail.SmtpServer = "smtp.gmail.com"

Sub SendMail_Gmail()

'Declaro variables

Dim Email As CDO.Message

Dim Autentificion As Boolean

'Creo el objeto email

Set Email = New CDO.Message

'Ponemos datos del servidor a usar

Email.Configuration.Fields(cdoSMTPServer) = "smtp.gmail.com"

Email.Configuration.Fields(cdoSendUsingMethod) = 2

'Indicamos el número de puerto smtp

Email.Configuration.Fields.Item("http://schemas.microsoft.com/cdo/configuration/smtpserverport") = CLng(465)

'Decimos si requiere o no autentificación 1 requiere, 0 no requiere

Email.Configuration.Fields.Item("http://schemas.microsoft.com/cdo/" & "configuration/smtpauthenticate") = Abs(1)

'Segundos de espera

Email.Configuration.Fields.Item("http://schemas.microsoft.com/cdo/configuration/smtpconnectiontimeout") = 30

'Definición de verdadero para la autentificación

Autentificacion = True

'Configuramos el ingreso al mail

If Autentificacion Then

    'nombre de usuario

    Email.Configuration.Fields.Item("http://schemas.microsoft.com/cdo/configuration/sendusername") = "TUCORREO@GMAIL.COM"

    'password

    Email.Configuration.Fields.Item("http://schemas.microsoft.com/cdo/configuration/sendpassword") = "TUCONTRASEÑA"

    'si el servidor utiliza SSL (secure socket layer). en gmail: True

    Email.Configuration.Fields.Item("http://schemas.microsoft.com/cdo/configuration/smtpusessl") = True

End If

' Una vez configurado nuestro servidor de correo tomados datos de excel para enviar el mail

    'Correo del destinatario

    Email.To = "DESTINATARIO@DOMINIO.MX"

    'Dirección del remitente

    Email.From = "TUCORREO@gmail.com"

   ' Asunto

    Email.Subject = "Prueba de email smtp"

   ' Mensaje

    Email.TextBody = "Hola Destinatario, esto es una prueba para enviar un correo por smtp. Saludos"

   'Este es en caso de que quieras enviar un archivo

    'Email.AddAttachment "C:\Program Files (x86)\Zebra Technologies\ZebraDesigner 2\Samples\Database\CARS.xls"

   'Actualizamos datos antes del envio

    Email.Configuration.Fields.Update

   'Controlo errores

   On Error Resume Next

   'enviamos propiamente el mail

    Email.Send

    'Si no hay errores la funcion es verdadero

    If Err.Number = 0 Then

       MsgBox "Mensaje Enviado"

    Else

     'msgbox con descripción del error

       MsgBox "Se produjo el siguiente error: " & Err.Description, vbCritical, "Error nro " & Err.Number

   End If

   'Borro los objetos

    If Not Email Is Nothing Then

       Set Email = Nothing

    End If

    'Controlo errores

    On Error GoTo 0

End sub

Private Sub EnviarCorreo_Click()

Dim CDO_Mail_Object As Object

Dim CDO_Config As Object

Dim SMTP_Config As Variant

Dim Email_Subject, Email_Send_From, Email_Send_To, Email_Cc, Email_Bcc, Email_Body As String

    Email_Subject = "Tratando de enviar email usando CDO"

    Email_Send_From = "xxx@hotmail.com"

    Email_Send_To = "yyy@gmail.com"

    'Email_Cc = "databison@gmail.com"

    'Email_Bcc = "databison@gmail.com"

    Email_Body = "Felicitaciones!!!! You have successfully sent an e-mail using CDO !!!!"

    Set CDO_Mail_Object = CreateObject("CDO.Message")

    On Error GoTo debugs

    Set CDO_Config = CreateObject("CDO.Configuration")

    CDO_Config.Load -1

    Set SMTP_Config = CDO_Config.Fields

    With SMTP_Config

         .Item("http://schemas.microsoft.com/cdo/configuration/sendusing") = 2

         .Item("http://schemas.microsoft.com/cdo/configuration/smtpserver") = "smtp.live.com"

         .Item("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate") = 1

         .Item("http://schemas.microsoft.com/cdo/configuration/sendusername") = "xxx@hotmail.com"

         .Item("http://schemas.microsoft.com/cdo/configuration/sendpassword") = "zzzzzz"

         .Item("http://schemas.microsoft.com/cdo/configuration/smtpserverport") = 25

         .Update

    End With

    With CDO_Mail_Object

         Set .Configuration = CDO_Config

    End With

    CDO_Mail_Object.Subject = Email_Subject

    CDO_Mail_Object.From = Email_Send_From

    CDO_Mail_Object.To = Email_Send_To

    CDO_Mail_Object.TextBody = Email_Body

    'CDO_Mail_Object.cc = Email_Cc 'Use if needed

    'CDO_Mail_Object.BCC = Email_Bcc 'Use if needed

    'CDO_Mail_Object.AddAttachment FileToAttach 'Use if needed

    CDO_Mail_Object.send

debugs:

If Err.Description <> "" Then MsgBox Err.Description

End Sub