For some PCs, at least. Windows 8.1 August Update launched last week, with appropriate fanfare, and even though it seemed that everything worked fine, some issues have been reported.
Pretty serious issues — a number of computers are failing to boot.
Blame it on some modifications made to system files, or something, but it turns out that some PCs that upgraded to this new version of the operating system cannot boot anymore. Still no idea whether this is a widespread problem, or only affecting certain configuration of hardware.
Nevertheless, there is a pretty long thread over at the Microsoft Community forums. This is what the user reporting the problem said:
“I installed all of the august 12 updates today, after the first reboot everything seems fine. After a second manual reboot that wasn’t requested, the system shows the initial flag and loading throbber, then kicks to an all black screen and gets no further.
System restore fixed the problem, I have reinstalled some of the updates so far, and found some are ok, but at least two are definitely still causing this black screen on second reboot.”
The problem has been traced to KB2975719, which as you may be aware is actually the Windows 8.1 August Update pack itself. So the issue could be rather serious, for some.
Best to avoid this update for a while until Microsoft provides detailed information.