Unfortunately, I´ve the same problem and haven´t been able to solve it. After updating to v.17.6.2310(build 17.6.3625.0) both browsers, IE and Chrome stopped working. After uninstalling Avast, they work, after installing avast again, they stop:-(
I use WIN7Home premium. Both Chrome and IE are at the newest versions.
Please, is there any solution for this, I haven´t found any:-( Thanks alot, LR