Hi,Lately, I have been experiencing a strange occurrence, for which I found no explanation. It happened around the time there were some Windows updates, about one week ago. You will find a list of these updates at the end of this message.The computer (specs also at the end of this message) works perfectly, and gets updated regularly. All hard disks (internal as well as external) are SSDs.The occurrence can be described as follows: at shutdown, either normal shutdown, restart, hibernate or sleep, the operation goes apparently well - until the moment the machine has to shut down completely, which normally occurs almost instantly after the necessary time to clean up things and whatever chores are left to allow the OS to terminate its functioning - like the display shutting down properly, as well as the (external) keyboard and so on. But now, to allow the complete shutdown, it takes about 75 seconds minutes for the machine to do so. This very long time does not seem to affect further functioning of the computer: neither on reboot, restart, or waking up from hibernate or sleep.So, nothing dramatic, except an annoyance but I fear that when time will come to upgrade for example to Win 11 with its numerous restarts and so on, this late total exit might be a problem.

I have also a feeling that, when starting up, after the welcome screen things take longer than usual to completely load up, but not as long as the complete shutdown as described above. And now and then some apps do not seem to function as quickly as they did. But this can be a false impression, which I cannot quantify anyway. And today, a new occurrence, which might or might not be related to all this, took place: some minutes after startup, things seem to freeze, and none of the apps seem to react, while operations (even a simple cut and paste) seem to take many seconds to be accomplished. But when things return to normal, after about 1 minute, everything works totally normally. The momentary freeze occurs apparently when I open the Chrome browser - but I can not ascertain this for 100%. I just mention the occurrence for complete information.

I have tried many remedies I found on the web - described among other sites in:
Shutting Down Doesn’t Fully Shut Down Windows 10 (But Restarting Does)
How to Fix When Windows Won’t Shut Down

And I have run an exterior virus scanner (Malwarebytes) because my machine is protected by MS Defender, which up to now seems to have done its job without a hitch...

Nothing seems to help. And I am passably baffled.

Very recent app installations don't seem to be involved, because the slow total shutdown began to occur before the latest installs. The only certainty of a more or less precise moment of the start is around the latest Windows updates last week between 11 and 13 August. You will find the list of these updates at the end of this message. But I wouldn't bet on these updates to be the cause of the problem. But one never knows.

I will be grateful for any hint or solution and would be loath to redo a full Windows installation but such an annoying but non catastrophic situation.

Best regards and thanks beforehand,

Haku

List of mentioned specs and Win updates

Win updates (around the time the slowdown began to occur)
Quality UpdateUpdate for Win 10, version 21H1August 13, 2021—KB5005033OrDefinition UpdateSecurity intelligence updates for Microsoft DefenderAugust 11, 2021—KB2267602OrOther UpdatesWindows Malicious Software Removal Tool x64 - v5.92August 13, 2021-KB890830OrCumulative Update for .NET Framework 3.5 and 4.8 for Windows 10 21H1August 11, 2021—KB5004331

Win version number etc.
Edition Windows 10 HomeVersion 21H1Installed on ‎6/‎10/‎2020OS build 19043.1165Experience Windows Feature Experience Pack 120.2212.3530.0

Device specs:
Device name DESKTOP-4U982DLProcessor Intel(R) Pentium(R) Silver N5000 CPU @ 1.10GHz 1.10 GHzInstalled RAM 4,00 GB (3,83 GB usable)Device ID 81A8B6F7-A91F-4103-A0AA-085AC5FEF2EBProduct ID 00356-02081-64119-AAOEMSystem type 64-bit operating system, x64-based processor