I checked my Update history and noticed that the Definition Update for Windows Defender - KB2267602 failed to install. I do not use Windows Defender as I use Norton Security. Windows Defender is grayed out. However, I think that the definitions should install anyway.
Another problem is that W10 does not tell me why It failed. If I remember, under W8.1 I always got the error code to help me troubleshoot the problem.
Anyone have any idea on what is going on and how to fix it?
Z
I don't know, if the Defender updates should get downloaded and installed - after all, they will not be used at all.
However, in Windows Update there will now be a "Retry" button. And on top of that button there will be the name of the failing update and directly behind it there should be an error code. At least that is how Windows Update looked when it failed for me (which was ... yesterday).
I don't see a retry button. I ran a Check for Updates and all is up to date so I guess the Window Defender update does not mean much. I also have a KB3087040 (Flash Player update) that has four entries - failed to install, failed to install, installed, failed to install. I guess I will just keep my eye on these updates to see what happens. If the Window Defender Definitions fails again, I will try a couple of the suggested fixes on Google.
Z
Many folks including myself had issues with the latest IE Flash Player update.
I just retried and it installed successfully, after repeated fails the last day or two.
I did not install the "fix" for this, i just did another "Install Updates", and it worked for me.
See this thread: Fix for Flash Player Security Update install failure on Windows 10 - Windows 10 blog
I don't know why you would get WD definition updates if you installed another AV (Norton).
imho, WD should get disabled, and i would expect that would include definition updates.
If you have a Win 10 version (Pro or Enterprise) that has Group Policy edit, maybe something can be done ?
I'm interested in the answer to this.
I'm using WD now, but considering using a different AV such as Panda or Avast.
My only thought was that if I had a problem with Norton Security and decided to remove it, Windows Defender would kick in with the latest definitions.
Like I said earlier, If the update fails again next month, I will look into some manual fixes for it.
BTW: I did find something in Google where it said that CCleaner could cause a problem with Windows Defender so I unchecked Windows Defender in CCleaner so CCleaner will not do anything to the Windows Defender processes.
Z
I agree, if you uninstall a 3rd party AV, it should re-enable WD, including definition updates.
New WD Definition Updates are published daily (many new definitions per day).
No need to wait till next month to test that.
I can't comment on using CCleaner with a 3rd party AV on W10.
On W10 I'm using WD now, and i do use CCleaner (portable) file cleaner.
FIX: I was able to fix this by opening CMD as Admin and typing (with quotes):
"%PROGRAMFILES%Windows DefenderMPCMDRUN.exe" -RemoveDefinitions -All
Then I typed (with quotes:
"%PROGRAMFILES%Windows DefenderMPCMDRUN.exe" -SignatureUpdate
Hope this helped!
Thanks for this info! Worked for me too!