Windows 10 - Windows Defender not working

[scionluna]

Hello,
I need some help in restoring Windows Defender.
It is turned off even after uninstalling Norton Security.
I tried following a few suggestions from the Microsoft Tech Support Community and neither works.
The first solution was to change the input values in the registry for Windows Defender but in each case, I receive a message saying "Cannot write values into registry".
The second was to rewrite the registry for Windows Defender but I keep getting an error saying "The file is not supported" even though the file is a registry file.
Thank you for the help.

 

[RumoredNow]

Give this a try: System file check (SFC) Scan and Repair System Files & - Microsoft Community

Sounds as if there is a corrupted file somewhere.

 

[scionluna]

@RumoredNow, I forgot that on my list.
I did run a SFC scan and it corrected an error. But I still cannot run Windows Defender.