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One of the most annoying habits in Windows 8 is, that the built-in "Antimalware Service Executable" (part of "Windows Defender") starts hogging my device's CPU with 60-70% (and 100% disk) for extended periods EACH AND EVERY time after I wake it up.
I wouldn't mind if it starts doing its business IN THE BACKGROUND but when I wake my device up from standby it's usually to get something done NOW and thus I find it increasingly unacceptable, that the system is always taken over by Window's defender exactly then and for up to several minutes! If I don't find a solution soon to throttle this beast, then I will disable Defender altogether!
What I noticed is, that this process seems to be actually triggered not by the system waking up, but by the network adapter becoming active. And actually, this happens each and every time ANY network adapter gets active! E.g. if my system has NO network connection at all and I plugin the network cable the Antimalware Service Executable starts. When - after it has settled again - I additionally enable Bluetooth then the Antimalware Service Executable starts its hogging business again. And if I then additionally enable the WLAN a few minutes later, it will AGAIN start to consume CPU!
So: can one decouple this? Running a scan ONCE after (re-)starting it is definitely enough, especially if Defender hasn't downloaded any new signatures since the last run! And, second, can one make Defender convince to strictly run in the background ONLY?
Michael
[Moved from Windows]
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
oh, and I actually went to the trouble of making a damn Microsoft Account just so I could make the above comment. I appreciate just what a frustrating issue this is and ultimately ended up downgrading to Windows 7 as Defender is one of several issues I had with the OS.
After following everything said in this thread, the quickest, easiest, and most surefire way of stopping Defender from needlessly hogging your CPU is to disable it completely. Do this by opening Defender from the Control Panel (right click the start button), click on the settings tab and disable real time protection by unchecking the box, then under Administrator uncheck "Turn on this app". You should get a box appear telling you that Defender is now disabled. Restart your PC and bask in the glory of being able to utilise all your CPUs power.
If you ever need to re-enable it then this can be done from Control Panel/Action Centre, but I advise downloading a free alternative such as Avast or AVG instead. [Insert comment here about Microsoft making their end user's systems vulnerable to attack/infection due to bad programming].
I did this and it STILL is hogging my computer! Grr!
And so.....do u have any help on this issue?. So ur point is leave box checked to only run when on ac power. So that won't stop scanner from running, but what will. Should install third party AV?. Would that disable Microsoft one, or is their a box, or setting to stop scheduled scans?. Maybe its the scanning of incoming internet traffic which is causing it to bog down computer?. Is defender program just not any good?. Does someone have any actual answers to this problem as ut is very annoying.
There isn’t any one-size-fits-all solution for this issue, because there are lots of different things that can put the Microsoft antimalware engine into a frenzy. There’s a long history of CPU utilization problems with the Microsoft Antimalware Service Executable (MsMpEng.exe) going back to the days of OneCare. The magnitude of the problem seems to have largely abated with MSE, but that’s at least partly due to the fact that MSE has a CPU throttle for its scheduled scan. So it’s very possible that the Microsoft antimalware engine is still a little more sensitive to underlying issues than the engines of other AV products.
My approach has always been to first make an honest effort to fix the problem before moving on to another AV solution, and that’s the approach that I’ve taken in my previous posts in this thread (see those posts for the answers to some of your questions). But looking at the “falling-baseline” test scores for Microsoft AV products, I’m inclined to believe that people shouldn’t waste a whole lot of time trying to make Windows Defender behave before they move on to a better-rated alternative like Bitdefender Free or Panda Free. On the other hand, it’s always wise to make sure that every last trace of any previously installed third-party AV product is removed before installing another third-party AV product – so if you do that while Windows Defender is still enabled, you’ll at least be able to see whether or not that might be the underlying issue.
GreginMich
And so.....do u have any help on this issue?. So ur point is leave box checked to only run when on ac power. So that won't stop scanner from running, but what will. Should install third party AV?. Would that disable Microsoft one, or is their a box, or setting to stop scheduled scans?. Maybe its the scanning of incoming internet traffic which is causing it to bog down computer?. Is defender program just not any good?. Does someone have any actual answers to this problem as ut is very annoying.
