Here is some more information:
Microsoft software update breaks Windows 7 on some PCs
A certain patch prevents Windows 7 PCs with specific types of motherboards from booting.
http://www.cnet.com/news/microsoft-software-update-breaks-windows-7-for-some-users/
It appears that Win7 users having done the install of KB3133977 will cause non-booting or crashes. Depending on how you word it, the PCs based on an ASUS mtrbd. will be at the core of the problem due to the KB# being installed. The UEFI status is changed or becomes active for "secure boot" that the update will turn-ON or similar. In other words if you have Win7, Asus mtrbd., UEFI active(secure boot) in bios and install the KB#, you will be hosed.
http://www.infoworld.com/article/3065487/microsoft-windows/recommended-kb-3133977-patch-can-cause-asus-pcs-to-freeze.html
While this article explains the issue, other similar hits by googling can offer a fix. I suggest you do and see what works for you. Of course, back-up critical or important data before any fix is applied.
FYI- MS supposedly knew about the issue and offers that Win10 is now more palpable to move to. ![]()
tada -----Willy ![]()

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