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There are a wide range of system settings controlled by a PC's BIOS. These settings are typically accessed by pressing a specific key while the PC is booting (F2, F8, F12, DEL) to access a text screen where you can view and change system settings. Changes are stored in non-volatile memory so they persist across restarts and even when power is off.

One important setting available on most current PCs is a setting for what state to go into after power is cut off then restored. Having this option set to either "ON" or "Previous State" (i.e., come back on if the PC was on when the power was cut) can allow you to resume using the system remotely without needing physical access to press the power button. When setting up a PC that you'd like to be able to access remotely, it's a good idea to set this to "On" or "Previous State."

You can only access the BIOS text screen locally at the keyboard during restart, not remotely. In the event you want to check or modify a BIOS setting without rebooting, even from a remote session, some major vendors provide interfaces to access and update BIOS settings from the running Windows O/S without rebooting. (We're not aware of comparable tools for Linus or MacOS.) 

Please proceed carefully in attempting to modify any BIOS settings; read the vendor's instructions carefully. You may need administrator access to install and run these utilities. Also, if you have set a BIOS password, you will need to enter that to change BIOS settings. Some utilities may require you to set a BIOS password prior to making other changes. If you do so, please notify your supervisor of the BIOS password!

This page has a broad selection of BIOS-related PowerShell commands specific to Dell, HP and Lenovo PCs:
[[http://www.systanddeploy.com/2019/03/list-and-change-bios-settings-with.html|BIOS access in PowerShell]]

If your PC was custom built from parts with a system board by Asus, MSI, or other brands, these steps would not apply. You could check the board vendor's website to see if they have a comparable utility.

===== Steps for checking and setting power state after power loss =====


==== Dell ====

Dell offers a series of "Dell Command" utilities. There is a package for Windows PowerShell called "Dell Command | PowerShell Provider"

Here are the steps to install this tool in Windows on any Dell PC, and use it to inspect and change BIOS settings on Dell PCs. These commands can be run in a remote session.

Use "Run as Administrator" to launch an admin PowerShell (or PowerShell ISE)
At the PS prompt, type

PS> Install-Module -Name DellBIOSProvider -Force

The PS namespace will now include "DellSmbios" for use with "get-Item" and "set-Item"

To view the current setting of AcPwrRcvry for system behaviour after power interruption, type:

PS>  get-Item -Path DellSmbios:\PowerManagement\AcPwrRcvry

While typing you should see drop-down autocompletion suggestions as you go through the parts of this path.
If it reports "On" then you are fine. If it says "last" the system will come back on if it was running when power went out.
If it says "off" then you will want to modify it to "On" (or "last"). Here is the command to do that:

PS> set-Item -Path DellSmbios:\PowerManagement\AcPwrRcvry "On"

==== HP ====

You can download the installer for HP's BIOS configuration Utility for Windows here:
[[https://ftp.hp.com/pub/caps-softpaq/cmit/HP_BCU.html|HP BIOS Config Util]]
When you run this installer, it unpacks the utility, suggesting directory path C:\SWSetup\{package ID}
You can replace that with a simpler path such as C:\HPBIOSConfig

Once the utility has been extracted, open an admin command prompt (search "cmd" - right click on Command and choose "Run as Administrator")
In the admin command prompt window:
%  cd C:\
%  cd HPBIOSConfig   {the folder where you extracted the utility}
%  dir   { locate the file named BiosConfigUtility64.exe }
% BiosConfigUtility /getvalue:"Power state after power loss"

Look at the list of available settings "CDATA[Power On, Power Off, *Previous State]"

The option with an asterisk in front is the current setting. 

If your current setting is "Power Off" you need to change this to "Previous State" or "Power On" to retain remote access after power interruption.

HP's utility requires that a BIOS password be set in order to make changes to BIOS settings.
Follow the instructions in this PDF to set a BIOS password [[http://ftp.hp.com/pub/caps-softpaq/cmit/whitepapers/BIOS_Configuration_Utility_User_Guide.pdf|HP BCU docs PDF]]

and then do  /setvalue:"Power state after power loss","Previous State"


Please notify your supervisor of any BIOS password you have set so your PC can be maintained once you leave.