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![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(185.6, 54%, 27%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EDA%3C/text%3E%3C/svg%3E)
We are getting this error message intermittently when sending email via System.Net.Mail through Office 365 SMTP
ERROR System.Net.Mail.SmtpException: The server committed a protocol violation The server response was:
at System.Net.Mail.SendMailAsyncResult.End(IAsyncResult result)
at System.Net.Mail.SmtpClient.SendMailCallback(IAsyncResult result)
No changes from our current configuration etc. Configured Tracing on System.Net and System.Net.Sockets and there are no exceptions being logged.
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(128, 8%, 22%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EA%3C/text%3E%3C/svg%3E)
O365 is not currently supported here on Q&A. The product group for Office 365 actively monitors questions over at
https://techcommunity.microsoft.com/t5/office-365/ct-p/Office365
--please don't forget to upvote and Accept as answer if the reply is helpful--