SmtpException: The operation has timed out RRS feed

  • Question

  • Hello All,

    Need some help here.

    I have a project where I have to migrate my application from Windows 7 to windows 10. I have a .net code which is running on the old servers to send an email in case a particular task is performed. I am getting an error as below: 

    The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.1 Client was not authenticated

    The new servers are connected to the SMTP servers for sure as I am able to send email using a vbscript and also I am able to telnet the internal SMTP server using the port 25.

    Monday, July 1, 2019 2:47 PM

All replies

  • Hi abhinav,

    Thank you for posting here.

    For your question, I want to know if this code has no problem in windows7. If your code works in window7, it gets and error when you migrate it to windows 10. I think it is not related to c#, you could post it in the following forum. 


    Best Regards,


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    Tuesday, July 2, 2019 8:38 AM
  • Hello,

    Are you doing this authentication http://www.systemnetmail.com/faq/4.2.aspx

    Please remember to mark the replies as answers if they help and unmarked them if they provide no help, this will help others who are looking for solutions to the same or similar problem. Contact via my Twitter (Karen Payne) or Facebook (Karen Payne) via my MSDN profile but will not answer coding question on either.

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    Tuesday, July 2, 2019 9:34 AM