Puede utilizar el siguiente código a modo de ejemplo.
(Esta función ha sido probada por nuestro personal de sistemas)


<%


'*****************************************************************************
'*
'* Function: SendMail
'*
'* Description:
'*                              Sends an e-mail
'*
'* Parameters:
'*                      - varFrom
'*                      - varTo
'*                      - varSubject
'*                      - varBody
'*                      - varMime ("HTML" or "PLAIN")
'*
'* Returns:
'*                      In case of success: 0
'*                      In case of error: The Err.Number
'*
'*****************************************************************************


Function SendMail(varFrom, varTo, varSubject, varBody, varMime)
        Dim iMsg, iConf, Flds

        Set iMsg = CreateObject("CDO.Message")
        Set iConf = CreateObject("CDO.Configuration")

        Set Flds=iConf.fields

        Flds(" http://schemas.microsoft.com/cdo/configuration/sendusing ") = 2
        Flds(" http://schemas.microsoft.com/cdo/configuration/smtpserver ") = "mail.unlugar.com"
        Flds.update

        With iMsg
        Set .Configuration = iConf
        .To = varTo
        .From = varFrom
        .Sender = varFrom
        .Subject = varSubject
        End With

        If varMime = "HTML" Then
                 iMsg.HtmlBody = varBody
        Else
                 iMsg.TextBody = varBody
        End If

        iMsg.Send

        SendMail = Err.Number

        Set iMsg = Nothing
        Set iConf = Nothing

End Function


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