I have COPPA Turned off, User Moderation Turned Off, E-mail Verification Turned on.
When the user Receives the E-mail for E-mail Verification and clicks the links.
What I did to find out that it was causing the problem was Set the user for Awaiting E-mail Verification, Choose Email Codes to User. Then took that link and clicked it.
FYI It Activates them fine. But they are on a white page with that error