Hi
     my mail server setting are okay i will show you the screen shot but my site is unable to send email to user for registration , listing etc i know it is related to cpanel setting and osclass but server side ok and osclass is up to date what should be the reason of that please help me in this regard thanks.
in screen shot port is 25 but i have tried 465 and other too and also i have tried it with ssl  when i send test email to any email it working but its not sending any email to user for their activity.

@hayat
Contact your hosting provider and ensure SSL certificate for mail match to your mail server. There are new security updates in osclass (check their forums).