Windows Defender ERROR: "Your system administrator has restricted access to this app"

Question

_{Tuesday, March 14, 2017 4:11 PM}

Hello everyone!

So i'm getting this error every time i try to start Windows Defender. This error started after my PC got infected with some virus, but i got rid of that virus with a different antivirus, and now Windows Defender wont start

All replies (13)

_{Tuesday, March 21, 2017 7:17 AM ✅Answered}

Hi davydel,

It seems that you have configured the gpo to disable Windows Defender. Please remove the gpo then check the symptom again.

Best regards

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_{Tuesday, March 14, 2017 4:27 PM}

Hello everyone!

i got rid of that virus with a different antivirus, and now Windows Defender wont start

What is the name of that "different antivirus" ?

It is most likely that program you installed has turned off Windows Defender.

I maybe outdated. In the past, Norton and McAfee will shut down Windows Defender, just to name 2. There are others that will do the same.

P.S. It could be that the virus was NOT completed removed. The "left behinds" are creating that issue.

_{Wednesday, March 15, 2017 6:25 AM}

Hi davydel,

There is only one antivirus software running on the machine at a time. If you have installed a third party antivirus software, it will block the Windows Defender automatically.
If you want to use Windows Defender, we could uninstall the third party antivirus software and restart the machine then check the symptom again.
 
Best regards

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_{Wednesday, March 15, 2017 1:12 PM}

the problem was the same before installing the antivirus... and windows defendes should tell me that: "you have a different antivirus sotware, windows defender turned off" or something like that.

best regards,

David

_{Wednesday, March 15, 2017 7:03 PM}

The Antivirus i currently have is Bitdefender Antivirus Free Edition. I know about that WIndows Defender turns off when there is another antivirus installed and i had the same problem before installing bitdefender. Anyways, if i try to open windows defender when i have a different antivirus installed it should tell me that i have a different antivirus software and that windows defender was turned off because of that and send me tot the page where i can uninstal the current antivirus that is on(i remember that's  what windows defender was doing when it was working and i was having avast installed... after uninstalling avast, it worked) but now it only says 

"Your system administrator has restricted access to this app"

with or without any other antivirus.

P.S: how can i make sure the virus was completely removed?

Best regards,

David

_{Wednesday, March 15, 2017 7:31 PM}

..........P.S: how can i make sure the virus was completely removed?.............

I'll leave this question to the "security" experts.
It can be a tedious process by applying different programs.
I am not well versed in this topic.

Please wait a bit and someone will come along.

Good luck.

_{Wednesday, March 15, 2017 9:13 PM}

P.S: how can i make sure the virus was completely removed?

'nuke the entire site from orbit. It’s the only way to be sure'

_{Thursday, March 16, 2017 8:37 AM}

Hi davydel,

Is this a domain environment?

For the Windows Defender error, please open an administrator command line and run "gpresult /h C:\gpresult.html" to check whether there is an applocker or Software restriction policy applied to the machine.

“how can i make sure the virus was completely removed?”
It is hard to confirm this. To ensure the scan quality, please perform a full scan with the antivirus software in safe mode.

Best regards

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_{Sunday, March 19, 2017 8:08 PM}

hi MeipoXu,

did the thing in the command line with the command and it generated the report.. where should i look in the report to see if there is any applocker or Software restriction policies applied? this is what i see regarding Windows Defender:

_{Monday, March 20, 2017 6:47 AM}

Hi davydel,

Is this a domain environment?

Check whether there is any gpo in Policies\Windows Settings\Security Settings

If it is possible, please upload the gpresult to OneDrive and paste the link here. I will check the gpresult for you.

Best regards

Please remember to mark the replies as answers if they help.
If you have feedback for TechNet Subscriber Support, contact [email protected].

_{Monday, March 20, 2017 5:06 PM}

Here is the link for the gpresult: https://1drv.ms/u/s!AtU67Gk3YSVlhCHV6kTrYhyWYED8

_{Friday, March 24, 2017 9:49 AM}

Finally got it working after disabling those 3 settings.. Thank you very much MeipoXu.. 

_{Saturday, May 19, 2018 3:00 PM}

I have got all of the same issue exactly after uninstalling Avast Free antivirus. The problem is, that there is no way to get to "gpresult /h C:\gpresult.html" result/file. When I am trying to run it, it will just make a blink of something on the desktop and then nothing is happening or opening. I have tried to disable temporary Avast (I have re-installed it later on) and tried to open the address above, but all in vain.

Hope for a simple-to-get solution, please.