Outlook Add-ins Crash Internet Explorer
Again another golden oldie I cam across. A client was integrating their CRM plugin with Outlook 2013 (In this example it was SalesForce, however they have since notified me that all add-ins from the Microsoft store also crashed Internet Explorer).
When they opened up an email and hit the CRM button, Internet Explorer would crash with the following error:
App Crash, Internet Explorer.exe Faulting Module :ierutill.dll Problem version of IE 11.9600.16428
After disabling and re-enabling various plug-ins I got the the source problem, UAC. It turns out the client disable UAC via GPO, because of this the add-ins seem to have issues speaking to IE.
As you can see from above the UAC is disabled, we set the UAC to Default and applied, upon testing the add-ins in Outlook again they all functioned correctly.