Explain me why a newbie like me can remove norton family in 2 min

Hello

I was wondering why my son spent more and more time in his bedroom and i've discovered that norton family was removed from his computer

I'm administrator ( even in safe mode ) on his computer and he has a limited account and of course he doesn't know my password

He's got like me only basic knowledge on computers

in fact he explain me that it is very easy to remove

you go in program file

norton online

engine

2.1.0.23

 

you rename or delete CCL100U.DLL

 

 

you reboot the computer and there no more internet family and no message is sent !!!!:

 

I've tried on my daughter computer and it works very well

I can't believe that such a sofware is so easy to remove and  I think I've made a mistake during the installation

 

could you give tell me what's wrong ?

Thank you