fixed problem (after several other failed attempts) by uninstall and reinstall.
Online Security add-on makes Internet Explorer 11 stop working on Windows 8.1 Pro 64 bit when IPv6 is enabled. The same add-on works fine on Windows 7 Home Premium 32 bit connected to same home network. After I enabled IPv6 on my modem/router using instructions from internet service provide, Internet Explorer 11 stopped working, but only on the Windows 8.1 box (which is 64 bit OS). The Windows 7 box (which is 32 bit OS) is happy running Internet Explorer 11 with Online Security add-on.
I got Internet Explorer 11 running on the Windows 8.1 box by disabling Online Security add-on.
The Action Center, problem details are below:
Source
Internet Explorer
Summary
Stopped working
Date
8/24/2014 11:56 AM
Status
Report sent
Description
Faulting Application Path: C:\Program Files\Internet Explorer\iexplore.exe
Problem signature
Problem Event Name: APPCRASH
Application Name: iexplore.exe
Application Version: 11.0.9600.17239
Application Timestamp: 53d22ad9
Fault Module Name: ntdll.dll
Fault Module Version: 6.3.9600.17114
Fault Module Timestamp: 53649e73
Exception Code: c0000005
Exception Offset: 000000000004d91c
OS Version: 6.3.9600.2.0.0.256.48
Locale ID: 1033
Additional Information 1: c5ce
Additional Information 2: c5cef47b29b538c5955223d3aba42214
Additional Information 3: eda3
Additional Information 4: eda3f1f2713094014f58bfb3e46d919c
Extra information about the problem
Bucket ID: ab5a427c756c63971232edb730fb73f0 (85949341036)