I've been having this problem for about a month now and it's annoying as hell.
Randomly while browsing the internet, installshield updater will crash and with it will go my internet connection. My tray indicated that I'm still connected to the internet but I am not. My PC is hardwired, first to the modem and now through an N600 router but that makes no difference. Everything else on my network remains connected.
Disabling and enabling my onboard ethernet doesn't work, and when I use a wireless connection with a USB adapter the same thing happens. The only solution is to restart the PC and works again as tho nothing happened... until Installshield randomly crashes again.