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I have an HP PC, that is running Windows. After a power loss, the computer turns back on, and I want to disable it.

I tried the BIOS, and the setting of "After Power Loss" is already Off (see image). I also tried changing that setting to On but that still made the computer turn on after a power loss.

enter image description here

How can I set my computer to not automatically power on after a power loss?

EDIT:

  • BIOS updated to latest version
    • Boot after power loss: Off
    • Network boot: Off
  • Replaced the CMOS battery
  • Tested even with no USB devices, just VGA and Power

Testing fashion: Turn on, pull the power cord, plug the power cord. Wait 2 seconds, then it boots again.

Still no luck.

Edit 2

If I unplug while running, then wait 5 minutes, then plug again, it does not boot until I press the boot button. What is going on?

Amit
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    This is the correct setting. Try setting it to on, exit and save, reenter bios, then set to off again, exit and save. If that doesn't help, ensure that the pc is in a grounded poweroutlet. – LPChip Feb 05 '17 at 10:24
  • @LPChip Did that, still no good – Amit Feb 05 '17 at 10:24
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    We have computers that do this, and if the bios setting is disabled, then 99% of the time it's related to the CMOS battery not holding a charge. We swap out the CMOS battery and that fixes it. – Austin Feb 07 '17 at 18:25
  • Check for a BIOS update. We can help in that if we knew the exact model. – harrymc Feb 07 '17 at 20:31
  • @harrymc BIOS updated, no luch there – Amit Feb 07 '17 at 21:41
  • @Austin Thanks, that is currently the only direction I can try. I will update when I get a replacement. – Amit Feb 07 '17 at 21:42
  • @Amit, why not trying just simply without CMOS battery at all? (just to test it sooner before new battery arrives.) – Yisroel Tech Feb 08 '17 at 01:05
  • @Austin Replaced the CMOS battery. No luck. See edit – Amit Feb 11 '17 at 18:21

5 Answers5

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Option #1:

In your bios you should have a 'power on by RTC' and 'Power on by pcie', have you tried disabling those? I believe they should be disabled by default.

Option #2:

Install and Configure a UPS Software

Step 1: Install PowerChute or similar software.

Step 2: Navigate to the Energy Management tab or similar within the Configuration setting.

Step 3: Check the Enable Energy Management checkbox and choose the Default settings in PowerChute. Look for any "Turn On Again" settings in any other power management software and check/uncheck as appropriate.

Option #3:

enter image description here

enter image description here

Option #4:

The .reg files below are for the registry key and value below.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\CrashControl

AutoReboot DWORD

0 = Disable
1 = Enable

Option #5:

In command prompt enter the following:

wmic recoveros set AutoReboot = False
DeerSpotter
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Try checking your Wake on LAN settings in your BIOS and OS (in this case Windows). I have found sometimes my computer would wake after being turned off because the implementation of Wake on LAN would trigger even if the device just received a directed packet towards it.

Though it might not relate to specifically the same HP computer as the one you have (or even the same version of Windows), you might find the article HP PCs - Computer Turns On Unexpectedly (Windows 8) useful.

As with most un-intended behaviour I'd also suggest updating the BIOS just in-case it was a known bug.

Matthew1471
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  • Turned off wake on LAN, that link is for sleep mode it seems, as for a BIOS update, it seems to always fail, I will give it several more tries – Amit Feb 07 '17 at 21:18
  • BIOS updated, no luck – Amit Feb 07 '17 at 21:41
  • @Amit, so there is an updated BIOS available, it just fails? You should check out why that happens. – Yisroel Tech Feb 08 '17 at 01:07
  • @YisroelTech As updated, BIOS update was available, updated, it still boots after power loss – Amit Feb 08 '17 at 05:26
  • I know it isn't useful in this state but as a pure diagnostic test, if you schedule a shutdown to occur in say 30 seconds (using the "shutdown /s /t 30" command) and then were to unplug your network connection and USB devices etc. (the bare minimum you can get down to) does it come back on or stay off :)? Also clutching at straws, Windows Update? – Matthew1471 Feb 08 '17 at 10:52
  • and another straw, any Scheduled Tasks defined with the "Wake the computer to run this task" option (particularly ones that are set to run every 15 minutes etc)? – Matthew1471 Feb 08 '17 at 10:58
  • @Matthew1471 No Ethernet, no USB devices. Still no luck. see edit – Amit Feb 11 '17 at 18:22
  • Have you considered something electrically wrong? i.e. the power button I wonder if that's shorting which would trigger it to go on. Are you able to remove the connection between the motherboard and the power button temporarily and see? – Matthew1471 Oct 20 '17 at 17:33
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Briefly, how are you testing this? I think the best way would be to power off the PC from windows and then unplug the PC. Hit the power button once or twice with while its unplugged to clear the capacitors. Then plug it in.

Does it power on immediately?? If so it has to do with the "After Power Loss" BIOS setting. If it powers on after a few moments or minutes it could the NIC or USB device waking the PC.

Also, is there a "Last State" option for "After Power Loss"? That setting puts the PC back to the last "State" it was in when it lost power- so if it was already powered down it would be the equivalent of setting it to "Off". Perhaps that option will function correctly since the others don't seem to?

Tyler M - Sea
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  • This might seem weird but are you booting into Windows via UEFI?

    Maybe it needs to fully boot into Windows first? That would be really weird to be honest.

     – Tyler M - Sea Feb 15 '17 at 23:39
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You could check in the BIOS for an entry for Advanced Power Management or ACPI with an option like Restore from AC power loss.

If that does not help, start a Command Prompt (cmd) that is Run as administrator and enter :

bcdedit /set {default} bootstatuspolicy ignoreshutdownfailures

For more information see the Microsoft article BCDEdit /set.

harrymc
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on HP pc simply turn off "wake on keyboard button" save, re-enter bios its not greyed out anymore.

(i just make an account just to answer it. LoL)

Kucing Ganteng
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  • I have an HP EliteDesk 800 G2 Mini and this was the answer I was looking for. had no idea that "wake on keyboard" disabled the power loss setting and was tearing my hair out looking for the solution on the web. – eil Sep 02 '23 at 19:57