[fatal1980]

Originally Posted by Milad

Sending a "hello" trial on every single message is more server intensive than retrieving only the bounced messages from a pop mail.

You're running a cron to process the messages from a pop account. Your method, takes more code, and more time to process messages. Your method works, however is inefficient and takes longer.

Instead you could have levels of verification. I'm assuming you're using the mail function to just blindly send the message along. Instead you could use sockets and make a connection to the mail server, try and send the message and if it doesn't go through then you don't need to generate an email. Otherwise you can just send the mail and process the bounce message. Also, you don't really need to use a POP Account. For linux users you could use a .forward file that pipes the mail to a script. Usually shared hosting providers have a mailbox setup on the local machine for each account, or for big boards that run VIPS or have a Dedicated Server.

Originally Posted by TooTall52

This won't work accurately as many email servers out there accept all mail, process it then kick back bounces for the invalid ones. microsoft exchange works this way for example, may Lotus Notes as well.

so just because a helo passes does not mean it is valid address, the seperate pop account is probably more accurate.

TooTall52

Yes, another reason why bounce back spam invades mailboxes. A properly written or configured MTA would do checks at SMTP time. And reject messages that it doesn't relay for, and for non-existent email addresses.

If the MTA accepts the message, and generates a bounce back afterwards. Spammers could use a forged from address, and now your server is spamming. Bad. In any case, if you're making a add-on that is going to change or improve the vBulletin mail portion then you should consider all the factors in making it secure and not server intensive.

You must understand that I'm only discussing this with you as general feedback. I praise anyone that provides modules for free to the vbulletin community and I thank you for your effort.