If you want to run the Enhanced Mitigation Experience Toolkit (EMET) 5.2 on Windows 8.1, you need to download the new version -- which is virtually indistinguishable from the old version.
Microsoft on Friday released EMET 5.2, which adds a few features to the venerable but touchy system-hardening package, and hardly a minute passed before bug reports were appearing online.
It seems that EMET 5.2 caused IE11 running on Windows 8.1 to crash. According to poster AnaBna on the TechNet forums:
Using Windows 8.1 with Internet Explorer 11, EMET 5.2 causes Internet Explorer to crash just by navigating to a website. I'm using 'Recommended Security' settings in EMET, with the default 'Popular Software' protection profile.
1) Open Internet Explorer
2) Either go to a website such as http://www.amazon.co.uk/ or alternatively just open IE and wait for 30 seconds without doing anything
3) Browser crashes and says 'Internet Explorer has stopped working'
Numerous posters confirmed that IE11 on Windows 8.1, running with EMET 5.2 in its default configuration, stopped IE11 dead in its tracks with no warning. Apparently customers could manually overcome the problem by disabling the Certificate Pinning check in EMET 5.2, but running bone stock on Microsoft’s latest versions of Windows and IE crashes IE.
On Monday, Microsoft updated the TechNet announcement article with this advice:
We have received reports of certain customers experiencing issues with EMET 5.2 in conjunction with Internet Explorer 11 on Windows 8.1. We recommend customers that downloaded EMET 5.2 before March 16th, 2015 to download it again via the link below.
Following the download link confirms that the version number remains at 5.2, with a filename of EMET 5.2 Setup.msi -- just like the original EMET 5.2.