It's most likely not nefarious. The combination of your email deliverability and people's laziness will mean that a lot of people probably won't click the acti

It's most likely not nefarious. The combination of your email deliverability and people's laziness will mean that a lot of people probably won't click the activation link. How are you sending email? Are you using AuthSMTP or something like that, or are you just doing it straight from your server? Is your SPF record correct? Have you tried a Port25 scan? You're not an average web user. For a lot of people, checking email is a separate activity from web browsing. If they use Outlook, they have to open a completely separate program just to use your site. They don't have GMail open in a separate tab at all times. I would wonder if you really need people to activate their account that early in the process, but I'm not that familiar with how your site works.