It is always very ****ty when you send mail from a browser. The connection, browser, and OS are always a factor. The host could restart the box, or your life just sucks. But if you have millions of users, or even 5000. Or in my case, 19,600 who desire to receive your email. If the browser closes on accident, or there is a power cut due to thunder, etc .. And you're already at 15,000 then restoring a session of the browser won't help. It's a POST input only accepting state thingymebob. Result: you're screwed. In my case 4,500 didn't receive their mail, unless I accept the risk of having to re-mail the mail to the first 15,000. It would be nice if the mail simply has a 'state' and a table where it stores the submitted mail. So when you come back at any point it says: 'mail is in progress, 15,000 out of 19,600 [attempt to continue] [close mail job].