Windows Defender in Windows 8.1 Will Not Turn On

I have 8.1 and use AVG free edition and it has worked for me for years. Automatically updates and works just fine and NO viruses.  Go to AVG website and download the FREE edition, they will try to sell you other but just watch your screen and get the free one. The download should go to your Desktop or Downloads folder, then you install it from there, very easy and a great anti-virus program.

As for Windows Defender, I understand it will NOT work if it identifies that you have OTHER antivirus software. In my case I had Win 8 - upgraded to 8.1 and the when the Win 10 became available I upgraded to 10. Then found out that it is a total SPY program and is sending info about you every minute of every day, I went back to 8.1 which I am using now, and it will only get an error if I try to activate Windows Defender anyway.

I have not used Defender for 2 years and don't miss it.

I trust AVG.

Bob

Did you ever get IE11 working properly? => http://answers.microsoft.com/en-us/ie/forum/ie11-iewindows8_1/internet-explorer-11-cannot-load-any-page/7f3f95f3-9fc8-492d-96db-b4fbc69fb8bd

Hi Michael,

It would be great if you can provide more information regarding this issue. Please answer these questions for a better understanding:

1)       Are you able to open Windows Defender program on the computer?

2)       If yes, what exactly happens when you turn it ON from its user interface? Do you get any error message?

I would suggest you to try the following methods and let’s know the results.

Method 1: Start the Windows Defender Service Manually

Please follow these steps:

 a)       Press “Windows Logo” + “R” keys on the keyboard to open the “Run” command box.

b)       Type “Services.msc” in the “Run” command box and press “Enter”.

c)       In the “Services” window, search for the “Windows Defender” service from that list.

d)       Double-click on it to open its “Properties” window.

e)       From its “Properties” window, click on “Start” when the service is stopped and also change its “Startup Type” to “Automatic”.

f)        Click on “Apply” and “Ok”.

g)       Restart the computer and check if that resolves the issue.

If the issue still persists, then try the next method.

Method 2: Run Windows Defender as Administrator

a)       From the Windows 8 Start Screen, type “Defender”. Windows Defender should appear in the list.

b)       Right click on the “Windows Defender” icon and select “Run as Administrator” from that menu.

c)       Check if that launches Windows Defender on the computer and check if you are able to turn it ON.

Please get back to us with the results.

none of the two solution solved the problem and windows defender is still not on any other suggestion to turn it on?

@Gingerlane

I have seen this posted several times as a fix.  Though my problem is not exactly like the OP problem.  I still get error code 577.  Windows Defender does not exist in "windows features" for my case.   When using the steps you have shown it will not finish its boot when I click start.  I did a sfc /scannow check and no problems found.  I did a dism.exe check no issues found.   When I try to open windows defender I get "To allow this app to run, contact your security administrator to enable via group policy".  I have windows 8.1 I did not upgrade from windows 8.  It was already on My Lenovo G50.

So far I have seen no solutions without having to get into registry and rewrite things that "may" work.  I have not seen confirmation that my windows version has resolved issue by rewriting the shown registry section said to be corrupted by anti-virus programs.  Miss windows 7 :) 

Windows 7 seemed to finally be finished with all the kinks worked out only to jump into 8, 8.1, 10 with new kinks and less privacy.  Sometimes I even miss having to use The disks that use to come with computer.  It felt like you owned what you bought, but I digress.

Have you found any solid solution for Error 577 windows defender problem for 8.1.

oops did not click notify me when someone responds and the option was not available in edit.  so I posted this as a reply to hopefully fix my mistake.  I do wish to see response to question.