Activation code expires in 24 hours!
 

By default, the activation codes sent to new users expires after 24 hours. How can I disable this time-limit so that new users can activate their account whenever they wish?

It is a very poor setting on default vBulletin to expire the activation codes in one day, this hardly gives the users a chance to come back and activate their account and actually will drive users away when they can't complete their registration.

anyone know in which vB file this setting is coded in?

This is actually a very needed security measure. A normal user who wants to register on a forum does not wait a few days before activating. and they can always request a new activation code.

Why is it such a security risk if a member decides to check their email 2 days later?

u can also take a look at this thread:

http://www.vbulletin.com/forum/showthread.php?t=293927

Why would someone register and wait a few days before activating in the first place?

People are lazy, sometimes they don't bother opening their Emails until the next time they feel like it.

Well when they do open their emails, they simply request a new activation code, it takes 2 seconds, and press the link in the new email.

It may seem simple to you, but people don't like reading long error-messages and it can be a big turn-off, especially at the crucial time of registration. I would agree with you, but I'm speaking from the perspective of real users, it's what I've found from experience of dealing with new members.