I realize my last post might have been missleading. This is a feature of cpanel 11 that is being used by many servers. It is actually a program called "Sender Verify". I am not sure if this is available to the public to help protect their forms or just a feature available to cpanel when installed on a server, but it would be fantastic if we could use something like this in a form, wouldn't it?
How Does It Work?
When an email is received from exemple@domain.com, the mail server application (Exim for example) immediately contacts the sender's server (domain.com) and asks it to confirm the existence of user example@ on its server. If confirmed, the email is
assumed to be legitimate and passes the Sender Verify test. Otherwise, the mail is rejected and the sender receives notice of this rejection via an email containing the error message that the email was not valid, or something like that.
I copied some of this text because the explanation was better than my own words.
The sad part is that not all domains accept this, so some valid email addresses may get blocked. I hope that explains it better.
I think Plesk pannel might have something similar, at least in the newest versions.
Sender Verify never sends an email to the email address. It is just checking to see if there is the possibility that the email exists on that server/domain. It is better than the typical php email validation, which as stated only checks for the proper format, and not the existance of the email address.
E-Learning Specialist
www.mainsites.ca is my website, and yes, some of it is crappy.