I have a 3-day old clean install of Windows 10 Pro x64 version 1511. This is sysprep-ed install with 'Users' folder relocated to D: drive.
This install, as I suddenly discovered, suffered from the following issue:
- When I started Windows Feedback app, it presented me with a "Sign in" button. Hitting that button did nothing. The button blinked, but nothing happened.
- In Store app, when I opened the menu and selected "Sign in" nothing happened.
- When setting up Cortana, when I got to the point where it asked me to sign in, hitting the "Sign in" button did nothing.
Meanwhile, apps like Contact Support worked fine - they asked me to sign in and I signed in successfully.
It appeared that all apps that were supposed to use this standard "Choose an account" dialog
were "broken". The dialog did not appear and sign in simply did not work. All other apps seemed to work fine.
Doing SFC, DISM and stuff did not help at all.
So, I decided to do another clean reinstall of the same system in order to figure out at what stage that "Sign in" would die. And I did reinstall it, going through my standard procedure of doing sysprep in order to relocate 'Users' folder to D: drive. The install went through smoothly. But immediately after the first boot the problem was already there (!). Right away, on a perfectly clean spanking new install I was already unable to log into Windows Feedback because the "Sign In" button did not do anything.
I thought that maybe my sysprep was to blame here. However, I have another machine that was installed from the same image and sysprepped in exactly the same way. And it does not have that issue. The only difference that other machine has it that it uses a WiFi connection, while this problematic one is connected by Ethernet.
So, I guessed that maybe because this problematic machine get access to Internet very early, some update or something else sneaks in very early and ruins the install. To test this, I disconnected the cable and repeated the clean install from scratch, again with sysprep and 'Users' relocated to D:. And viola! The machine installed perfectly and the above problem was gone.
To test this I repeated the clean install in the following combinations: 1) cable in, sysprep, 2) cable out, no sysprep.
It appears that the problem occurs only when the machine is connected to network during sysprep. Such installs of Windows 10 1511 end up with broken "Sign In" functionality in some apps. My other, WiFi, machine installed fine because it, obviously, had no network connection at sysprep stage. I still don't know whether it is caused by a mere network connection or specifically by Internet connection. Figuring everything out would require a lot more tests.
But the morale of the story is: if you are doing a sysprep on an Ethernet-connected machine, disconnect the cable and plug it back it only after the sysprep stage.