On Sunday, October 22, 2017, a massive Windows 10 update came down to my computer.
After about an hour and an unknown number of restarts (I went about my day doing other things), everything claimed to have been installed and I was able to use the computer.
I powered down the computer like I always do before going to bed.
This morning, October 23, 2017, I powered on the computer.
Everything seemed normal except after entering my PIN, instead of taking me to my desktop, the screen just stood there, dumb as a box of hammers.
I hit the ESC key on my keyboard, which brought up the login screen where, for the second time, I entered my PIN.
This time it logged me in.
WinVer revels I now am running the 64-bit edition of Windows 10 1709 OS Build 16299.19).
A few minutes later, I saw a notice "You Need Some Updates", so, I launched the normal "Check For Updates" and found a number of updates still "Pending Installation" and some were "Pending Download".
I clicked the buttons necessary to download or install and waited patiently for it to finish (or at least CLAIM it was finished).
Nothing exciting happened, but experience tells me that I should restart the computer, even if it doesn't tell me to do so because, as I just mentioned, having used Windows since 1987, more often than not, Windows Updates NEEDS the special circumstances of a full reboot to finish applying whatever patches were supposedly pending.
Even after rebooting, logging in STILL REQUIRES DOUBLE-ENTRY OF MY PIN.
My recommendation to anyone who has not "upgraded" to Windows 10 1709 (not sure I would characterize Windows 10 1709 using that word) HOLD OFF FOR NOW until Microsoft fixes this issue.
Moved from: Windows / Windows 10 / Install, upgrade, & activate