I have something similar to this. My users have a 9 digit "token" that is assigned only to them. If they don't enter it correctly, they don't register. I used the help of our friend Kyle to set it up. You can see the thread here:
www.joomlapolis.com/forum/153-professional-member-support/223186-solved-qsecuredq-registration
Once you are done doing that part, log into phpmyadmin open the database you're working on and select the comprofiler table. Find the field that you want to use and select the "U" on the right. This will create a "unique" value for that field. If you already have multiple same entries you will get an error saying it wont work and why. Clear those entries and do it again.
I am experimenting with this myself. So far I have not had any adverse reactions from doing it. Just be sure to
:woohoo: ***** BACK UP YOUR DATABASE BEFORE YOU START!!! ***** or you will be :sick:
I get a error message now when I try to enter duplicate value so it's working. I just need to figure out how to edit the error because it's not that pretty when it happens.
Good luck.
