EWS 2.0 und VS2010 (Basic.net)

Imports System.Net.Mail
 Public Function MailMessageAuth(ByVal _from As String, ByVal _to As String, ByVal _username As String, ByVal _password As String, ByVal _smtpserver As String, Optional ByVal _subject As String = "", Optional ByVal _body As String = "") As String  
        Dim client As New SmtpClient(_smtpserver)
        Dim mail_regex As New Regex("^[^\*\?]+@[^\*\?]+\.[a-z]{2,4}$", RegexOptions.IgnoreCase)  
        If Not mail_regex.Match(_from).Success Or Not mail_regex.Match(_to).Success Then
            Return "Error - Angegebene E-Mail-Adressen haben nicht das korrekte Format"  
        End If

        Dim m As New MailMessage(_from, _to, _subject, _body)
        Dim smtpUser As New System.Net.NetworkCredential(_username, _password)
        With client
            .UseDefaultCredentials = False
            .Credentials = smtpUser
            Try
                .Send(m)
            Catch ex As SmtpException
                MsgBox(ex.Message)
                Return "Error - " & ex.Message  
            End Try
        End With
        Return ""  
        '-------- Returns empty String if Mail was send successfully  
        '-------- Returns "Error - " + Description of Exception in case of error  
    End Function

MailMessageAuth("FROM", "TO", "USERNAME", "PASSWORD", "SMTP-SERVER", "SUBJECT", "BODY")