"Your organization manages certain settings"

I just managed to update... I don't know how, but the install updates button has been activated. However, the error message is still there.
Here are the 3 FRST reports:

Addition: https://pjjoint.malekal.com/files.php?id=20191111_o6i5u15y6c13
FRST: https://pjjoint.malekal.com/files.php?id=FRST_20191111_v5s9u614o15
Shortcut: https://pjjoint.malekal.com/files.php?id=20191111_x5o13x12y14z6

Thank you, I will try all of this!

There are malware.
You were tricked by an InstallCore installer, a PUP (potentially unwanted program) platform offered on download sites or through fake Java and Flash updates.
It suggests installing Chromium to force Yahoo!, Seguaro, Segurazo, Avast!, McAfee Security Advisor, or McAfee LiveSafe.
To avoid being tricked again, read: PUPs InstallCore

+ other malware.

You have programs that were installed when you purchased the computer or installed later that are not necessarily useful.
They clutter Windows and can slow it down.
You can therefore uninstall them.
Go to the Control Panel
then programs and features.
Uninstall:

Chromium
IObit Unlocker
McAfee WebAdvisor
Unchecky


Here is the fix to apply with FRST. You can refer to this explanatory note with screenshots.
Restart FRST, then on your keyboard press CTRL + Y.
The notepad will open, copy/paste this.

Start:
CloseProcesses:
CreateRestorePoint:
Startup: C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Startup\Windows Explorer.lnk [2018-11-29]
ShortcutTarget: Windows Explorer.lnk -> C:\Users\Gaël\AppData\Roaming\log\OfficeStarter.vbs (No file)
GroupPolicy: Restriction ? <==== ATTENTION
Task: {01E20F26-14D4-4A93-B549-ED55A6A3D3C3} - System32\Tasks\{207A875C-DE27-AD40-6C77-7B6A4D216BDA}\madorok => C:\Users\GAL~1\AppData\Roaming\207A87~1\madorok.exe
HKLM\SOFTWARE\Policies\Microsoft\Windows Defender: Restriction <==== ATTENTION
EmptyTemp:
RemoveProxy:
Hosts:
Reboot:
End:

Save the content from the file menu then save.

Close notepad, go back to FRST and click the "Fix" button.
A restart may be necessary and automatic.
A text file will appear, copy/paste the content here in a new message.

Restart the computer.

~~

Press Windows + R
type gpedit.msc and OK.
Expand on the left: Computer Configuration > Administrative Templates > Windows Components.
On the right, everything should be set to not configured.
You can change the status by double-clicking on it.

The same for User Configuration > Administrative Templates > Windows Components.

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If you can't reset, then

Reinstall Windows 10 without formatting:

The principle is to create a Windows 10 installation USB drive and boot the computer from it to reinstall Windows without formatting to keep your data.
Since the computer is frozen, you need to create this from another functioning computer.

To create the USB drive:

You need a USB drive of at least 8 GB.

• Create a USB drive with Media Creation Tool: Download and create a Windows 10 USB drive with Media Creation Tool
• Boot from it by modifying the boot sequence and select the USB or DVD: How to boot the computer from USB drive

If the USB drive doesn't work, try making one again with Rufus: how to download Rufus.
Download the ISO file, for example, with Adguard: Download Windows ISO
Launch Rufus, then specify the path of the ISO file
In partition scheme, choose GPT.
For more details, refer to this tutorial: how to create a Windows installation USB drive

The Windows 10 installer should then start:

Follow this tutorial that explains how to install Windows 10: how to install Windows 10.
All steps are provided from A to Z with tips at the end to secure Windows 10.

• Let yourself be guided to install Windows 10.
• Choose Custom (not Upgrade)
• During the partition phase, select the main partition and click Next.

• The installer will tell you that Windows is already present and will suggest moving it.

• Follow the Windows installation procedure using the tutorial above.

Just don't format.

Your user data will be copied to the Windows.old folder.

Once Windows is installed, I advise you to follow these tips to properly configure and use Windows: Tips after reinstalling Windows.

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