"Server does not support secure connections. " ?

hello
I use password recovery with SMTP. i have error at hosting that "Server does not support secure connections. "
my web.config is below
system.net
mailSettings
smtp deliveryMethod="Network" from="destek@interaktifilan.com"
network defaultCredentials="true" host="mail.interaktifilan.com" port="25" userName="destek@interaktifilan.com" password="****"
smtp
mailSettings
system.net

my hosting say me that "Please do not use Secure connection for SMTP. and Our mail server does not support secure SMTP connections." I dont know where i use secure connections. how can i find it and fix it ?
Thanks


 
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