Those registering with "yahoo, hotmail or similar" type account.....
 

BEFORE you try to register EMPTY your email box, I get a dozen requests a week from folks saying they "did not get the email confirmation" and "most of the time" it is someone using one of these type accounts.

From vBulletin support:
For what it's worth I get a lot of bounced emails from people who's mail boxes are full, 'unavailable' or over quota. This is a particular problem with hotmail and yahoo accounts. Unless you are on a dedicated server and can set where these bounce messages go, you will never see them.

other notes from vBulletin support:
"many of the people registering for my sites were not getting the confirmation email because of their ISP's spam protection"

Also this maybe your case:
"I have over 700 AOL users on my messageboard and NONE of them can recieve emails from my site.

No notifications, emails from the CP, etc etc

Im assuming that it is because AOL sees the Mailer as junk or spam mail."

Also IF you don't get the email confirmation and you email us about PLEASE include the "BOARD NAME" you registered with as there is no way for us to help unless we have this info.

Thank you

To get the email confirmation sent again......click this.