Adding this computer

I have Norton 360 on my windows XP SP3 system.  I installed safety minder 1.2.1.7 which I like very much & it worked well until I added another child's account to this computer.  Safety minder will not recognize the new account.  when I try to "add this computer"  It prompts me to uninstall (since the program is installed now)  I can not uninstall as the program will not recognize my password. 

Please let me know how to fix this.

Thanks

Eric