SMTP Ping Check

Question

HI,

 

 

    you provided SMTP ping check code in  below link

 

    http://www.c-sharpcorner.com/UploadFile/kirtan007/check-if-email-address-really-exist-or-not-using-C-Sharp/

 

    It is working only for  gmail accounts. Then i keep resolver for all email addresses but it is not working can you please provide code for this.