Some questions
Does it happen with all sites? Many sites? Just at HZ?
What Operating system is she using (Windows Vista? XP?)?
What browser(s)? (Version numbers too, please.)
By "unable to connect," does she mean connect to the internet in general? Or can she connect to the net, but not bring up the 'Zone?
Did she make any changes to her system (eg, install new software) around the time the troubles began?
Does she run anti-virus, anti-spyware software? If so, what does she use? Has she tried to do scans recently?