How to execute an application or batch file before Windows fully loads?

Question

System administration

You must run the application or batch file before Windows fully loads.
This feature is implemented in many disk partitioning programs. For example, when changing the size of the C drive, the partition manager reboots the system and almost at the beginning of Windows loading, its console application is executed, which is already quietly moving system files until they are locked.
Here is a demo:
www.youtube.com/watch?v=8A1uLE2dX0c&t=2m22s
www.youtube.com/watch?v=Doo7QHpOVZ4&t=3m57s

Answer 1

You must run the application or batch file before Windows fully loads.

It's impossible! No Windows application will run until the system boots.

This function is implemented in many programs for partitioning disks.

You misunderstand the situation - such programs work in the so-called Windows Preinstallation Environment (WinPe) is a lightweight version of windows that is completely located in memory, the same environment that is used when installing windows.
Many LiveCDs for system recovery, sets of utilities for maintenance, etc. are based on it.
In this environment, you can run disk partitioning tools, system utilities, networking tools, remote access tools (for example, teamviewer), etc.

Answer 2

The same Partition Manager can replace the standard chkdsk utility, which works "until it is fully loaded." You can also get out like that, although this is not very good and is most likely punished by the antivirus.

Answer 3

Here you can register programs that will be loaded until Windows is fully loaded. (For example, chkdsk is written here)
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\BootExecute:
Read more here, but this is after starting the services:
pashinblog.ru/sysadmin/run-on-load
Well, in fact, you can pick up the application as a service , prescribe autorun, and it will run before login