Windows 11 Not shutting down issue

[xendistar]

I have Windows 11 Pro installed on a Mini PC (came as standard). I access this windows PC from a Linux PC using No machine remote desktop access and this works well without issue.

I have a Schedule Task to shut the PC down at 10:30 every night, the trigger in the task is Shutdown /S /F and this has worked perfectly for many month until about two weeks ago when I would check and randomly find that the PC was still running but if I tried to login with NoMachine, it would not be able to make a connection, pinging the IP address gives a reply. My only option is to push the On\Off button to shut the PC down. The PC is up to date with Updates

I have looked in the Event Logs files but the only entry I find is as follows:

In the Security Logs I get at 22:30:32 An account was logged off

In the System Logs I get 22:30:34
The process C:\Windows\SystemApps\Microsoft.Windows.StartMenuExperienceHost_cw5n1h2txyewy\StartMenuExperienceHost.exe (MINI) has initiated the power off of computer MINI on behalf of user MINI\mit for the following reason: Other (Unplanned)
Reason Code: 0x0
Shut-down Type: power off
Comment:

@22:30:36 User Log-off Notification for Customer Experience Improvement Program
@22:30:36 User Log-off Notification for Customer Experience Improvement Program
@22:30:36 The system session has transitioned from 0 to 1.

Reason ScreenOffGracePeriod

BootId: 119
@22:30:36 The driver \Driver\ACPI for device stopped the power transition.
@22:30:36 The driver \Driver\ACPI for device stopped the power transition.
@22:30:37 The system is entering sleep.

Sleep Reason: Application API
@22:30:38 The system has resumed from sleep.

The last entry confuses me, why is it resuming from sleep when the instruction have been sent to shut the device down. Under Power options the option to put the PC to sleep is set to Never.

Can anybody advise what the issue is or where to look for additional information. Simply put, I want the PC to automatically shutdown if I forget to shut it down but I dont want to use the Power setting Option to shut the PCdown if there is no input for X hours

 

[ChatGPT]

What your log is showing is:

1. the scheduled task did run and issued a shutdown, but
2. Windows then transitioned into a sleep state instead of completing a clean power-off, and
3. it immediately woke again.

The key lines are:

• StartMenuExperienceHost.exe ... has initiated the power off
• The system is entering sleep. Sleep Reason: Application API
• The system has resumed from sleep

So the odd part is not the task trigger itself — it’s that something in Windows/firmware is diverting that shutdown into a sleep/modern-standby style transition.
A few likely causes:

1) Fast Startup / hybrid shutdown​

On Windows 10/11, a normal shutdown is often not a “pure” old-style S5 shutdown. Microsoft’s fast startup uses hibernation technology during shutdown, so shutdown behavior is not always as literal as it looks. Microsoft documents that fast startup uses hibernation infrastructure, and that power diagnostics should be checked with powercfg tools. Microsoft also documents /lastwake, /waketimers, /requests, /sleepstudy, and /systemsleepdiagnostics specifically for this type of investigation. citeturn0search11

2) Modern Standby / S0 low power idle​

If your mini PC supports Modern Standby, Windows can enter a low-power “screen off” state that behaves differently from traditional S3 sleep. Microsoft notes that in Modern Standby, the system can wake for maintenance, network activity, or other events even though the screen is off. citeturn0search0turn0search1

3) A wake source or power-management bug​

If the machine goes into sleep and instantly resumes, common causes are:

• wake timers
• network adapter wake
• USB wake
• BIOS/UEFI firmware issue
• chipset / ACPI driver issue
• a recent Windows update exposing a firmware bug

The ACPI lines in your System log make firmware/driver interaction worth checking.

What I would do first​

A. Check what sleep states the PC supports​

Open Command Prompt as Administrator and run:
powercfg /a
This will tell you whether the machine is using S3 or S0 Low Power Idle / Modern Standby. Microsoft’s powercfg documentation says /availablesleepstates reports the sleep states available on the system. citeturn0search11
If you see Standby (S0 Low Power Idle), that would fit your log much better than classic sleep.

---

B. Check what woke it​

Right after one of these failures, run:

powercfg /lastwake
powercfg /waketimers
powercfg /devicequery wake_armed
powercfg /requests

Those four commands are exactly what Microsoft exposes for:

• what woke the machine,
• active wake timers,
• devices allowed to wake,
• apps/drivers making power requests. citeturn0search11

What to look for:

• NIC / Ethernet adapter
• USB receiver / keyboard / mouse
• UpdateOrchestrator
• maintenance task
• “Wake source count 0” can still happen on newer systems, especially with Modern Standby behavior.

---

C. Disable Fast Startup​

This is the first practical fix I’d try.
Go to:
Control Panel > Power Options > Choose what the power buttons do > Change settings that are currently unavailable
Untick:
Turn on fast startup
Reason: Microsoft states that fast startup changes the default shutdown path to one based on hibernation technology rather than a full traditional shutdown. citeturn0search11
If your nightly shutdown starts working again after disabling Fast Startup, you’ve found the culprit or at least the workaround.

---

D. Change the task action slightly​

Instead of relying on the current form, make the Scheduled Task action:
Program/script
C:\Windows\System32\shutdown.exe
Add arguments
/s /f /t 0
That is cleaner than putting the whole string in one field.
You can also test:
shutdown /s /f /t 0
manually from an elevated command prompt at a convenient time and watch Event Viewer immediately afterward.

---

E. Generate the built-in power diagnostics reports​

Run these as Administrator:

powercfg /sleepstudy
powercfg /systemsleepdiagnostics
powercfg /systempowerreport

Microsoft documents all three as built-in reports for sleep transitions and power transitions. citeturn0search11
These reports often reveal:

• which component initiated the sleep transition,
• whether the system was in Modern Standby,
• what resumed it.

If your PC is Modern Standby capable, sleepstudy is especially useful. Microsoft describes SleepStudy as the built-in tool for viewing Modern Standby activity durations and causes. citeturn0search0

---

Things I would also check​

1. Network adapter wake settings​

In Device Manager > your Ethernet/Wi‑Fi adapter > Power Management:

• untick Allow this device to wake the computer
• if present, disable Wake on Magic Packet / Wake-on-LAN temporarily for testing

Since you can still ping the box when it gets stuck, network hardware is definitely still partially alive.

2. USB wake​

For keyboard, mouse, USB receiver:

• Device Manager > device > Power Management
• untick Allow this device to wake the computer

3. BIOS / UEFI update​

Because your log includes ACPI transition messages, a BIOS update is high on the list. Mini PCs often ship with flaky power-management firmware.

4. Recent update correlation​

Since you said this began about two weeks ago, check:

• Settings > Windows Update > Update history
• look for a cumulative update, firmware update, or driver update installed just before the problem began.

That date correlation matters.

---

Why “Sleep = Never” does not rule this out​

That setting only controls idle sleep timeout.
It does not prevent:

• an app/API from calling sleep,
• Modern Standby transitions,
• wake timers,
• hybrid/fast-startup behavior,
• firmware wake events.

Your log explicitly says:

Sleep Reason: Application API

So Windows did not go to sleep because of idle timeout; something called the power API.

---

My best guess​

Most likely order:

1. Fast Startup / hybrid shutdown interaction
2. Modern Standby / S0 behavior
3. Wake source from NIC/USB/update task
4. Firmware/ACPI bug triggered by a recent update

The fact that it worked for months and then changed points strongly to either:

• a Windows update,
• a driver update,
• or firmware state drift.

Recommended fix order​

If this were my machine, I’d do this in order:

1. Disable Fast Startup
2. Change the Scheduled Task action to:
   C:\Windows\System32\shutdown.exe /s /f /t 0
3. Run:
   powercfg /a
4. After the next bad event, run:
   

   powercfg /lastwake
   powercfg /waketimers
   powercfg /devicequery wake_armed
   powercfg /requests

5. Disable wake on NIC/USB for testing
6. Update BIOS/chipset drivers

If you want, I can turn this into a step-by-step diagnostic checklist or a forum reply draft you can post back with the exact commands and what output to look for.