[RESOLVED] system.IO.IOException

[viper5646]

Hi all
In the following Sub I'm sending an Attachment when the email has been sent I would like to delete the attachment but I get an system.IO.IOException Error. the file I'm trying to delete is being used by another process.
How can I detect if the process has finished.

Thanks
Happy New Year to everyone

Private Sub SendMail()
        Try
            Dim cfiAttach As Net.Mail.Attachment
            Dim Attacmentfile As String = AttDir & fileName & ".pdf"
            Dim SmtpServer As New SmtpClient()
            Dim mail As New MailMessage()
            SmtpServer.Credentials = New Net.NetworkCredential(diaSettings.txtMail_User.Text, diaSettings.txtMail_Pass.Text)
            SmtpServer.Port = smtpPrt
            SmtpServer.Host = SmtpHst
            mail = New MailMessage()
            mail.From = New MailAddress(Mail_user)
            mail.To.Add(Mail_TO)
            ' mail.Bcc.Add(BBC_MailTO)
            mail.Subject = fileName
            mail.Body = ""
            cfiAttach = New Attachment(Attacmentfile)
            If File.Exists(Attacmentfile) Then
                cfiAttach = New Attachment(Attacmentfile)
                mail.Attachments.Add(cfiAttach)
            Else
                MsgBox("Attachment Not Found")
            End If
            SmtpServer.Send(mail)
            MsgBox("Sent")
            System.IO.File.Delete(AttDir & fileName & ".pdf")
        Catch ex As Exception
            MsgBox(ex.ToString)
        End Try
    End Sub