Windows 10: Does Windows Defender auto scan files being downloaded through web browsers?

I have noticed (for quite long, decided to ask today out of curiosity) when files finish downloading in Chrome, the download progress bar stay at 100% for a bit before chrome says download is done. I have a habit of scanning every file immediately after download so I wanted to ask if I was performing redundant actions. Does Defender scan files as soon as they are downloaded or is that Chrome making sure all parts are downloaded?

The main reason this occurred to me is that if it was chrome making sure complete file is done, it would take longer on large files and not so much on small. That's not the case. Large video files are done immediately. But zip/rar archives take a bit of time if they contains a lot of small files. The amount of time take is pretty much consistent with how much time Defender takes on different file types. It mainly depends on number of files, not file sizes.

submitted by /u/iBzOtaku
[link] [comments]

:)

 

Windows 10 Defender scanning downloaded files

Running Win10 Home 64bit on a MSI Z270-A PRO motherboard, i7-6700, 16 GB ram.
This is a new build for me and I just installed Win10 Home and did all updates.

When I download programs with Defender running, do I have to manually scan the file before installing the program?

When I tried to manually scan a downloaded program using the following method, it doesn't show results of the scan:

• Rt click the file name.
• In the pop up menu, click "Scan with Windows Defender"
• A window pops up showing "Full Scan", "Custom Scan" and "Windows defender offline scan", but no results of the individual file scan.

Thanks for any ideas.

 

Windows 10 Defender scanning downloaded files

I have the same build as you. I think Defender does scan downloaded files but I scan them again anyway before installing to be sure.

 

Windows 10 Defender scanning downloaded files

Hi Steve,

I got a screen like yours one time during my testing but never again over a LOT of follow up testing. I have no clue why. I never get the "Threats found" and "Files scanned" info anymore no matter which file I try to scan.

I wonder if it's even necessary to scan files that are downloaded. AFAIK, Win10 Defender is supposed to have real-time protection so does it auto scan every file that is downloaded regardless of which browser is used to download? I'm running Firefox by the way.

My version of Win10 is: Version 1803 (OS Build 17134.407)
Run "winver" to see this.

Thanks for contributing,