Transaction failed. The server response was: Mail from itsupport@xxxxx.in rejected for policy reasons.
It clearly means that your email server did not allow email to be sent from the given email ID because of the policies defined by your mail server for sending an email. It can be because of any reason against defined policy like sending an exe file in email or some text in the email which is not appropriate. It might also happen that the user credentials are not authorized to do so.
Server dose not support Secure Connection
There are defined SMTP ports that allow secure connection. Looks like the port used to send email for SSL is not configured for the used port.
Make sure you have configured SMTP configuration correctly in Web.Config:
<system.net>
<mailSettings>
<smtp from="abc@somedomain.com">
<network host="somesmtpserver" port="25" userName="name" password="pass" defaultCredentials="true" />
</smtp>
</mailSettings>
</system.net>
If needed, have a look at this Microsoft Video tutorial:
Use ASP.NET to send Email from Website[
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