Microsoft Windows computers gave birth to the entire industry of antivirus, antispyware, internet security and what not. Then Microsoft started providing Windows Defender, which is a free software that provides an extra line of defense against spyware and malicious software. Windows Defender scans the computer’s hard drive to search for and remove a range of security threats, including spyware, viruses and malicious software — also known as malware. By removing these threats, Windows Defender speeds up computer performance and also prevents annoying pop-up ads that can ruin your Web browsing experience.
Other antivirus and antispyware software have started to become annoying. Due to increased competition, each antivirus or antispyware is trying to outdo each other by not allowing others to run when a particular is running and so on. I had a gamut of such software and then for some reason I had go back to Windows Defender, which I was unable to run because it would give an error like Error 577 or it would take me to the C:\Windows\System32 when trying to enable it.
I spent hours trying to resolve the issue by looking for resolutions in forums after forums and if you face similar issue, this post will save you a lot of time. I even saw in several forums people suggesting installation of “their” software or malicious software, which will lead you in a deep hole. There is no need to try hundreds of things and getting frustrated. The solution to this is simple.
How to Resolve Windows Defender Error 577:
If you’re trying to turn on Windows Defender on Windows 8.1 or Windows 8 or Windows 7 and you see errors like the ones mentioned below:
This app has been turned off and is not monitoring your computer
Windows Could not start the Windows Defender Service service on local computer
Error 577:Windows cannot verify the digital signature for this file. A recent hardware or software change might have installed a file that is signed incorrectly or damaged, or that might be malicious software from and unknown source.
The root cause is that the registry value has been changed to disable turning on Windows Defender and your antivirus or antispyware is the most likely cause. Follw these steps:
- First uninstall any other antivirus or antispyware you might have installed like McAfee, Avast, Norton, Comcast Complete Protection, Spybot Plus etc.
- Restart your computer.
- Go to regedit.exe and navigate to HKEY_LOCAL_MACHINE->SOFTWARE->Microsoft-Windows Defender. What the above antivirus/antispyware apps would have done is changed the registry entry to 1 for DisableAntiVirus and AntiSpyware. The value of 1 means True i.e. DisableAntivirus and DisableAntiSpyware are disabled. This is the root cause of the issue you’ve been having.
- You need to change it to 0 (zero) by doing a right click -> modify and changing value data. If you’re unable to change the value, you will have to restart in safe mode.
- Restart your computer.
- Now go to Windows Defender app or Action Center and you would be able turn on Windows Defender.
Is you still have issues, let me know in the comments section below.