Can't Turn On Windows Defender Firewall

I'm running Windows 10 Pro Version 2004 (OS Build 19041.508).
I'm trying to start the Windows Defender Firewall service but seems to be imposible.
I tried these:
1. Run Windows Troubleshooter (this is joke app!)
2. Checked Windows Defender Firewall Service's Properties. Service is stopped!
3. Edited Windows Registry and added full rights for ALL in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
4. Tried to enable Windows Defender Firewall Using Command Prompt
5. Tried to "Restore Firewalls To Default" from Settings.

No more ideas, could you please help me?

Hello @D a n and welcome to TF
Tried Turn On or Off Windows Defender Firewall in Windows 10

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Maybe option 5 or 6 to start with.

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I would also run "sfc /scannow" and DISM from an elevated powershell or command prompt to check your Windows system for error if above didn't work.
Turn On or Off Windows Defender Firewall in Windows 10

Thank you Steve
I tried all of these ... no results.
Finally I installed tweaking.com app and I risked to give full access to my computer. I was lucky, this solved my problem.
Thank you again
Dan.

D a n said:

Thank you Steve
I tried all of these ... no results.
Finally I installed tweaking.com app and I risked to give full access to my computer. I was lucky, this solved my problem.
Thank you again
Dan.

Hmmm, I wonder what the underlying cause was?

Thank you for the followup and glad you got it solved.

Try this lines on powershell
Get-Service Winmgmt | Start-Service -PassThru | Set-Service -StartupType automatic
New-ItemProperty -Path 'HKLM:SYSTEM\CurrentControlSet\Services\Winmgmt' -name Start -PropertyType DWord -Value 2 -Force
New-ItemProperty -Path HKLM:SYSTEM\CurrentControlSet\Services\MpsSvc -Name Start -PropertyType DWord -Value 2 -Force -EA SilentlyContinue | Out-Null
Get-Service MpsSvc | Stop-Service -PassThru | Set-Service -StartupType automatic
Get-NetFirewallProfile | Set-NetFirewallProfile -Enabled True

regedit this to
Software\Policies\Microsoft\Windows Defender _> DisableAntiSpyware > 0