Norton Family not working on PC

Hi,

I have a problem that NF is not working on my kids PC. It's installed and enabled but it's not doing anything ( no blocking for restricted sites , no monitoring for visited pages ..etc )

Although it's working good on his Android mobile phone. ( the problem is on the pc only )

I checked and followed the instructions here

https://family.norton.com/familysafety/help.fs?action=installingNSM#win

when I log onto the PC as the monitored child and when I try to access a forbidden website, No blocking at all.

The version of Norton Family running on the problematic pc is 3.4.0.43
The pc is running win7 professional 64bit / Firefox 38.0.5 / IE 11  ( not working on both FF and IE )

My child is using a limited windows account and I can see a pop-up message at lower right hand corner saying I'm being monitored after I log onto the PC as the child.

Any solution for this annoying problem ?

Thanks