Another fine mess by Microsoft...

Apparently people have been getting problems trying to install "Update for Windows 10 Version 1511 for x64-based Systems (KB3122947)". Apparently this has been caused by the previous update not preserving settings, and possibly s lot worse...

Just checked for updates and this update installed no problem on 32 bit win 10 pro without a reboot, maybe they fixed it now?

Maybe there's a difference between the 32-bit and 64-bit versions .

(The code will almost certainly be different, to take advantage of the enhanced instruction set on 64-bit).

Installed here on both 32 and 64 bit win 10 without issue...

Who knows the cause . It's a report by the OP, not a personal problem.

My post is still valid. The 32-bit and 64-bit versions almost certainly have different code. Whether either works or fails will depend on the individual target configuration.

I had the similar problem, 2 x 64bit PC's, 1 installed the update with no problem, the other would not install at all. The easiest way I found was to go here and download the file and install it manually which worked straight away:

https://catalog.update.microsoft.com

There have also been problems reported with the 32-bit version: http://answers.microsoft.com/en-us/insider/forum/ins... It is true that the instructions sets are different on 32- and 64-bit systems, and the compiler will produce different instructions for the same code, but this is unlikely to be the problem here. (Such an error in the compiler would surely have been discovered by now.) It is much more likely that it is just a simple error in the shared source code for both versions.

Aside from the recurring update issue with my Windows 10 installation, of Windows freezing/hanging directly after update requiring a hard reboot, KB3122947 works ok.

The problem does seem to be very specific to certain hardware/software combinations. I've yet to experience a piece of software that didn't suffer some bugs, so it's hardly a Microsoft monopoly.

3 out of 4 machines had the problem. I cant think of a common factor. Some machines have Intel processors and some have AMD; some have nVidia processors and some have AMD.