Microsoft Windows 10 OS users may be able to reclaim a lot of disk space on their primary boot drive. Reports indicate Microsoft Windows Defender, the default security solution, is arbitrarily creating multiple files that eat precious storage space needlessly.
A bug in Windows Defender, the security platform that installs with every Windows 10 installation, reportedly creates “hundreds of thousands” of files that occupy a lot of storage space on disk drives that boot Windows 10.
Windows Defender behind the sudden shortage of disk space?
Quite a few users of Windows 10 who rely on Windows Defender to shield their computers have witnessed a sudden reduction in disk space. The reduction seemingly occurs overnight.
Some users have claimed the bug in the antivirus platform creates hundreds of thousands, and sometimes even millions, of files. Although the size of individual files is quite small, thousands of such files end up taking up gigabytes of storage space.
Windows Defender bug fills Windows 10 boot drive with thousands of files https://t.co/958GCIkngP
— Nick (@Nick_nick310) May 6, 2021
The bug apparently creates small files ranging from 600 bytes to a little over 1KB. There’s no pattern to the names. These files do not even have an extension. They merely appear to be ‘MD5 hashes’.
It is important to note that not all affected Windows 10 PCs end up with thousands of files. The number of files, and hence, the amount of storage they occupy, varies wildly.
Some extreme cases had the files occupying 30GB of storage space. Needless to mention, users who use small-sized SSDs as boot drives could face problems.
How to prevent Windows Defender from creating unnecessary files and occupying disk space?
Windows 10 PC owners should first verify they are affected by the Windows Defender file creation bug. The program stores these arbitrarily created files in C:\ProgramData\Microsoft\Windows Defender\Scans\History\Store.
If the folder contains several files that seem like MD5 hashes, simply delete them, advise security experts. Thereafter, check which version of the security solution is installed on the computer.
— Alain Picard Web Engineering & Cyber Security (@APicard27) May 6, 2021
It seems Windows Defender engine version 18100.5 is responsible. However, users of older versions could also be affected. Moreover, the bug also affects some Windows Server versions.
Windows Defender Bug Fills Windows 10 Boot Drive With Gigabytes of Files https://t.co/EER9tBl6Dz
— Cory W (@velleity33) May 6, 2021
Some security experts claim Microsoft has addressed the Windows Defender file creation bug in version 1.1.18100.6. Hence an update could delete the files automatically. Windows 10 users can check their Windows Defender version by going to Windows Security, clicking on the Settings cog icon in the bottom left of the screen, and then selecting About.
If the page shows any number below 1.1.18100.6, then head over to Windows Update and click on the ‘Check for updates‘ button to download the latest “Security Intelligence Update for Microsoft Defender Antivirus” update. Do note, the update will require a restart to take effect.