How To Fix Windows Defender Antivirus Error 577?

 Windows Defender Antivirus Error 577

Windows Defender is the built-in anti-malware tool for the Windows operating systems. If you are getting the Windows Defender antivirus error 577 message, follow the troubleshooting steps given below.

Solution 1: Check Your Windows Registry

  • On your Windows computer, launch the Run command box by pressing the Windows + R shortcut keys.
  • Enter 'regedit' in the Run dialog box and click OK.
  • In the Registry Editor window, navigate to the 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Defender' file path.
  • Locate the DisableAntiSpyware and DisableAntivirus DWORD entries and give a double-click on them to change the DWORD value from 0 to 1.
  • Click OK after changing the DWORD value in the Value data field.
  • If you cannot locate the entries mentioned above, navigate to the 'HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender' file path.
  • Change the DisableAntiSpyware and DisableAntivirus entries. Close the Registry Editor window.
  • Go to the 'C: \Program Files\Windows Defender' file path and double-click MSASCui.exe to run Windows Defender.
  • This will fix the Windows Defender error 577.

Solution 2: Change The Security Permissions In Your Windows Registry

  • Open the Registry Editor window and navigate to the 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Defender' file path.
  • Right-click the Windows Defender key and select the Permissions option.
  • Click the Advanced button and select Add.
  • Click on the Select a principal link in the Permission Entry for Windows Defender window.
  • In the Select User or Group window, enter your user name in the Enter the object name to select field and click OK.
  • Ensure that your username is selected in the Principal section and select the Full Control checkbox underneath Basic permissions.
  • Click OK  Enable Inheritance.
  • Click Apply  OK to save the configured changes.
  • If the problem persists, remove the third-party antivirus software installed on your Windows computer.
  • If necessary, restore your computer to the previous version using a system restore point. If you need remote assistance to resolve Windows Defender antivirus error 577, click the call button available on the screen.


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