Windows Defender makes it painfully slow to access files

I'm new to using Defender. I finally got sick of AVG and dumped it. So I have Defender enabled with real-time protection, but now accessing files is unbelievably slow. I might as well have a virus at this point.

For example, I use a Nexus dock program which builds up the icons for my different apps I have in the dock. Every reboot, it needs to rebuild the app icons again as I hover over each tab. With Defender off, the icons build very quickly - just a few seconds. Same when I had AVG installed and running. As soon as Defender is enabled, it takes easily 10 times longer - to the point where I'd say it breaks my PC. Is this what people put up with when running Defender? Am I missing something?

I'm about to go shop around for another free antivirus option, but before I do I wanted to see if this is normal behavior. I saw some forum post elsewhere that suggested to exclude a ton of file types to make accessing them quicker, including .exe and a ton of other common files (jpg, txt, etc.) but at that point, I won't have any protection as everything will be excluded, lol.

And if it does this even just accessing app icons, what will it do when I download, copy, extract or run large files?

Are you having this problem specifically with Nexus or any program/file you need to access?

I would check out their forums and perhaps ask them if anyone else is having similar issues:
Winstep Forums Index page

In general. Not just nexus.

I have separate folders for each thumbnail icon group that I have Nexus use. So I opened up some of those those folders in Explorer - just a normal folder with a couple dozen thumbnail icons in them - and the images generate sooo slow with Defender on. With it off it's lightning fast. I tested how long it takes to generate a folder of around 75-100 icons once opened:

- With Defender real-time disabled: about a second
- With Defender real-time enabled - over 10 seconds

Of course once they are generated, opening the same folder again, they are already generated. But next time I reboot, it has to do it all over again. And if it's taking this much time just to generate a folder of tiny icons, what kind of performance will this have on the rest of my system?

The slow drawing/displaying of icons is a "known issue" for us, WD users. Depending on your hardware it can be almost unnoticeable to painfully slow. For instance, on this pc (Intel i7-7770 cpu - Mechanical HD), it's almost as fast as with WD disabled. At home with my older i7 5960-x, it takes its time. I have never understood why WD performance is so random and why MS doesn't change this. My advice is to set some folder exclusions inside WD for known safe folders of your choice. For instance, I have whole STEAM folder excluded because under WD it tends to lag down a bit too.

PS - If you have several folders with a lot of executables inside, it can be a pain in the ass to navigate through them with WD. You can run and do any operation with them even if the icon isn't displayed yet though.

PS2 - Funny thing there aren't so many good free alternatives to WD. Some of third party AV packages are just buggy or offer less protection than WD (believe it or not). Or just nag you ad nauseam.

PS3 - I have just found out that if you MANUALLY DO SOME QUICK SCANS, it lessen the slowdown all over the board.

I don't have any quantifiable data to back this up, but I found over time that WD uses less resources and is faster with read/write operations.

Likely it has to do with "learning" what is on your computer so it can make the next operation faster. But as I said I cannot say this for sure it is just something I noticed by keeping an eye on processes in Task Manager to see how much memory and CPU is being used by WD.

I also have a scheduled task for WD to do a quick scan once a day; not sure if that helps but overall things do seem faster.

Hi there
I think a possible explanation is that if you have a lot of files and a complete scan has never been done WD is doing a scan and so will depending on the speed of your HDD's / SSD's slow down I/O access while it's running.

I'd do a complete scan overnight and then try again later.
Also on a new Windows installation Windows itself could be creating an index for the Index this drive option.

WD itself isn't a major I/O bottleneck.

Cheers
jimbo