Repairing Windows Defender

[trevm999]

Tomorrow I have to repair a corrupted Windows Defender. When you try to open Windows Defender Setting, the mouse cursor start flickering and the Windows Defender process maxes out the CPU.

So far all I'm seeing online is to try a sfc /scannow, or run the Windows 10 installer. A nuke and pave won't be an option.

I'm thinking about going straight to running the installer since I haven't actually seen reports of sfc actually fixing anyone's Defender issues.

Anyone seen this before or have any suggestions?

 

[Porthos]

run the Windows 10 installer

And take the current CU with you on a flash drive. I disconnect from the net so it wont take so long.

A nuke and pave won't be an option.

Sometimes it is the only option that works. That is why MS added the ability to refresh/reset, MS knows "other" fixes might not work. Welcome to 10aggedon.

On the bright side, Better when the clients don't see that option on their own so we can get paid to do it for them.

 

[Sky-Knight]

Prothos has it all down, also... you may as well start the drumbeat now. Every customer must always be aware that nuke and pave is sometimes the only path forward. It's always the cheapest path forward. Reinstalling a station is a known process with a standard bill. Sitting there tinkering until it might work later isn't.

The fact of the matter is if you don't have the installation media and license anymore, you are no longer licensed to use that software. Read the EULA, and keep tabs on your stuff.

 

[Porthos]

Reinstalling a station is a known process with a standard bill. Sitting there tinkering until it might work later isn't.

Agreed.

 

[Krynn72]

Is it 1709 already? If not just do an in place upgrade to it and it's like a nuke and pave without the nuke.

You could also install a good antivirus instead.

 

[fincoder]

Is it 1709 already? If not just do an in place upgrade to it and it's like a nuke and pave without the nuke.

It doesn't matter if it already has the latest build. Doing an in-place upgrade with the same build still works, but instead of doing an upgrade it's a Repair Install. I've used it several times to fix problems.

EDIT: beaten by my eastern timezone colleague

 

[Porthos]

You can do this even if it is 1709, of course.

With a1709 iso.

 

[trevm999]

Sometimes it is the only option that works. That is why MS added the ability to refresh/reset, MS knows "other" fixes might not work. Welcome to 10aggedon.

Well, technically a nuke and pave is an option, but this was originally a fresh install, so it's not an option I want to take and then have this happen again.

 

[trevm999]

It is 1709, so an in place upgrade is what I meant by running the Windows installer

 

[Porthos]

but this was originally a fresh install

How long ago and is Defender the ONLY issue it has. What "other" security software does it have?

 

[GTP]

I've successfully used this to repair broken Defender on Windows 10. It's never caused an issue..yet.

**DISCLAIMER**
I have never used it on a business or critical system that I did not image or backup first.
Use at you own risk!

Save as .reg Right click and run as Admin

Windows Registry Editor Version 5.00

[-HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender]

Also, this may help?

https://docs.microsoft.com/en-us/wi...virus/troubleshoot-windows-defender-antivirus

 

[ComputerRepairTech]

Never seen it before, i remember malware bytes antirootkit having a fixdamage.exe that resets a lot of stuff with windows defender to default but I don't know if that will help here since your issue doesnt sound malware related but its a quick download and won't take long to give it a shot. I think tweaking all in one windows repair also has a defender reset feature doesnt it?

 

[Diggs]

Have you ran DISM yet? (I believe Defender is included.) It should have been used before sfc.

Dism /Online /Cleanup-Image /RestoreHealth

 

[trevm999]

It was the apparently classic problem of Windows Defender trying to scan itself. Added an exclusion via powershell for the windows defender engine.