Hi, I have an application where i have to check whether an email id is really existing or not.
1. Can we do this by sending a dummy packet first, and if it returns an error (Mail Delivery system) then Email-ID does not exists, if it is success then the actual mail should be sent. If so, how to get the return value of Mail Delivery System or
ServicePointManager.ServerCertificateValidationCallback = delegate(object s, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors) { return true; };
2. Heard Spammers do use VRFY command and check with DSN response(2.0.0 for user exist and 5.1.1 for user doesn't exists).
How to implement this through ASP.NET.
Awesome Coding !! :)