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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.
I have the same issue. On a daily basis, my 32GB ram, twin SSD, quad core 2.7GHz machine becomes unresponsive as "Antimalware Service Executable" takes 100% of my CPU, for many hours. It is not possible to stop this service. I tried the solution here:
http://hyrokumata.blogspot.com/2014/10/antimalware-service-executable-high-cpu.html
But it made no difference.
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Antimalware Service Executable is a giant pain when running Windows 8 on an older computer. The only thing I tried that also worked for me was to disable Windows Defender. I would be using it, if it weren't for the fact that it takes over at will and holds the processor hostage until I disable it. However, on my main desktop with an i7-4790K processor, unsurprisingly, this doesn't seem to be an issue.
IF you can PLEASE make it so that Defender DOES NOT run when on BATT power.
It DOES NOT respect the settings "Start only while on AC Power" -- it starts anyway.
F** this is so irritating.
