Can one prevent Antimalware Executable to start hogging CPU for extended periods each time some network adapter gets active?

Hi thanks, it also highlighted the drivermax start up which I have been trying to get at. Oh thats Vista

Seriously people, the "answer" here is a prank, and you shouldn’t be wasting your time with it. If this thread would have been moved into the Virus and Malware forum in a timely manner, then we’d be able to concentrate on things that might actually help. This is the kind of “answer” that quite often passes muster in the other Answers forums, and now it looks like we’ll just have to live with it here; because while we once had leadership that set a higher standard for this forum, that’s unfortunately no longer the case.

The worst part is that this "answer" doesn’t even come close to describing how Task Scheduler actually works, and that should be abundantly clear to anyone who’s at all familiar with this app. Now you’d think that this would include at least one moderator in the Windows forum, since Task Scheduler is an ages-old Windows app. So this is really sad.

In addition to giving us a fictitious method for “unscheduling” the Windows Defender Scheduled Scan task, this “answer” also falsely attributes the problem to a user-scheduled scan. Now Microsoft actually did later publish a (bogus) method for scheduling a scan in Windows 10 that asks the user to add a trigger to the Windows Defender Scheduled Scan task – but if the source of the OP’s problem was actually a Windows Defender scan, then it would have undoubtedly been the Windows Defender Quick Scan that Automatic Maintenance runs every day. That scan runs for everyone who uses Windows Defender.

Of course if you read this thread carefully, it should be obvious that the reason that the OP was seeing such a high CPU utilization with the maintenance scan (and also probably with other Windows Defender components; like the Network Inspection Service), was that he still had Security Essentials (or elements thereof) installed after upgrading to Windows 8:

What I find odd, is that there are TWO different paths to an executable of the same name MpCmdRun.exe, i.e.:

- c:\Program Files\Microsoft Security Client\MpCmdRun.exe

- c:\Program Files\Windows Defender\MpCmdRun.exe

Is this the same program or are these different programs and/or versions?

And if the original "answer" isn’t bad enough – we’re now being lectured on a “new and improved” Carte Blanche method for modifying the Windows Defender Scheduled Scan task’s Conditions:

You can uncheck all boxes as Tadasha suggests under Idle, Power, and Network. In my case, I only had the first checkbox under Power checked by default. I decided to instead check all three boxes under Idle and change 10 minutes to 30 minutes. You can do as you like.

How cool is that?

GreginMich

Hi Sam,

Thank you for sharing your part of query in Microsoft Community.

However, as per the age of the thread, I would recommend creating your own thread with all the necessary information intact to get the issue resolved. This way your issue will get the needed attention and targeted assistance from experts all over the community.

I would suggest you to refer to the following article for suggestions on asking questions on forums.

***Suggestions for asking a question on help forums***

Hope this information is helpful.

HI

I don't agree with you. Sam's issue is exactly the same issue discussed in the thread, same OS, same process consuming CPU etc.

If the thread is old and people are still posting in it, it's Microsoft's fault for not having fixed it after over 2 years, not Sam's fault, to me in makes perfect sense to gather all people with exactly the same issue in the same thread...

I am also facing this issue and have to restart my computer otherwise the process takes a whole core of my CPU... 

Cheers

The easiest way I have found to remove this without damaging anything (with there being no way to remove the program entirely) is to just go in like the main response says. Windows Key > Settings > type in "Administrative Tools" > Open Task Scheduler.

From there Navigate via Task Scheduler Library > Microsoft > Windows > Windows Defender.

In this screen you should see 4 tasks in the center of the screen above a larger box. There are three ways to handle this. You can either directly disable all four tasks by Ctrl + Clicking all 4 > Right click > Disable; you can go in through the options and uncheck all the active boxes through all the settings tabs; or you can take my favorite route and delete all the tasks entirely which does not crash your computer, change any other settings, or cause any major problems. It simply stops Windows Defender entirely and removes the issue of the executable taking up so much CPU and disk. To delete all four simply Ctrl Click all 4 > Right Click > Delete. Since doing this I have had no issues, I run a third party Anti-Malware software (which takes up 1% or less cpu during non-scan hours). And the dreaded Antimalware Service Executable takes up under 1% cpu all the time and no disk along with sub 100mb memory.

Hope this helps someone.

Unfortunately, none of those “methods” will stop Windows Defender entirely, and everything beyond disabling the Windows Defender Scheduled Scan task is overkill that will just mess up the maintenance tasks. The Antimalware Service Executable (the antimalware engine) is the core of Windows Defender. That process will still be running after you trash the maintenance tasks, and since excessive CPU utilization by MsMpEng.exe is usually caused by a conflict between Windows Defender’s real-time scanning module and components or remnants of a third-party AV app, rather than by the scheduled maintenance tasks, the CPU issue will likely persist.

Installing a third-party AV app is supposed to disable Windows Defender, but if you already have a third-party AV app installed and the Antimalware Service Executable is eating up CPU, then what you need to do is disable Windows Defender itself – not just the Windows Defender scheduled maintenance tasks. That’s the only way to stop Windows Defender entirely. You can do that in the settings in Windows 8/8.1 and you can do it with Group Policy in Windows 10:

http://www.tenforums.com/tutorials/5918-windows-defender-turn-off-windows-10-a.html

Some general guidelines for dealing with this issue can be found here:

http://answers.microsoft.com/en-us/protect/forum/protect\_defender-protect\_scanning/how-to-stop-antimalware-service-executable-from/a3a57d31-4687-43c0-b274-261da7d89245

GreginMich

The easiest way I have found to remove this without damaging anything (with there being no way to remove the program entirely) is to just go in like the main response says. Windows Key > Settings > type in "Administrative Tools" > Open Task Scheduler.

From there Navigate via Task Scheduler Library > Microsoft > Windows > Windows Defender.

In this screen you should see 4 tasks in the center of the screen above a larger box. There are three ways to handle this. You can either directly disable all four tasks by Ctrl + Clicking all 4 > Right click > Disable; you can go in through the options and uncheck all the active boxes through all the settings tabs; or you can take my favorite route and delete all the tasks entirely which does not crash your computer, change any other settings, or cause any major problems. It simply stops Windows Defender entirely and removes the issue of the executable taking up so much CPU and disk. To delete all four simply Ctrl Click all 4 > Right Click > Delete. Since doing this I have had no issues, I run a third party Anti-Malware software (which takes up 1% or less cpu during non-scan hours). And the dreaded Antimalware Service Executable takes up under 1% cpu all the time and no disk along with sub 100mb memory.

Hope this helps someone.