只能等到自行Time out,這會造成有些e-mail不對而造成錯誤信息
解決方式其實很簡單,將MaxIdleTime設為0還有ConnectionLimit設為1就搞定囉!
SmtpClient.ServicePoint.MaxIdleTime = 0
SmtpClient.ServicePoint.ConnectionLimit = 1
如果想看官網回報可以看這裡
SmtpClient does not close session after sending message...
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