I posted this earlier

Here is what I found at the ExpressJet forum

If you are trying to register for the forum, please read this post first before contacting us!

Earlier this month (August 2007) we stopped accepting registrations from the following email addresses:
aol.com
hotmail.com
yahoo.com

Why you ask? Because all of them block our server generated activation emails. In order to prevent spam bots on this board, we require that you activate your account by clicking on a link that is emailed to you. I was having to manually activate 5+ accounts per day from the emails listed above and it just got old!

Please use the email address assigned to you by your ISP. If AOL is your ISP, then please go to www.gmail.com and sign up for a free email account. gmail.com does not block these server generated emails, though you might need to check in your SPAM box!

Thanks for your cooperation!
__________________
Mike

Maybe try a different email like gmail for the application.