Cannot connect to google.com

Hi

i am having trouble connecting to google.com my computor is running quick heal 2013 secuirty when i try to connect to google it sends a message saying cannot conect to the web page i keep trying and some times it goes to google i have taken it back to the computor tech person and it works for hime at the store when i get it home some times it works but not every time and some times not at all just woundering how i can fix the problem

thanks

barney