The Silent Squeeze
Windows 11 utilizes the NTFS file system, which includes a built-in feature to transparently compress files and folders. This feature is designed to save hard drive space on smaller solid-state drives. However, this compression requires the CPU to constantly unpack and repack the data on the fly every time you access a file. If you are working with large video files or running high-performance PC games, this constant background processing can introduce noticeable stuttering and significantly increase load times. Sometimes, Windows 11 might automatically turn this feature on for your entire drive if it detects you are running dangerously low on storage space.
Unchecking the Box
To ensure maximum read/write speeds and stop Windows 11 from automatically compressing your files to save space, you must disable the NTFS compression feature at the root drive level.
Open File Explorer and navigate to This PC. Locate your primary system drive (usually Local Disk (C:)). Right-click on the drive icon and select Properties. On the “General” tab, look near the bottom of the window for a checkbox labelled Compress this drive to save disk space. If this box is checked, uncheck it immediately. Click the Apply button. Windows will prompt you, asking if you want to apply the changes only to the root folder or to all subfolders and files. Select Apply changes to drive C:\, subfolders and files and click OK. The decompression process may take several hours depending on the size of your drive, but once finished, your files will remain uncompressed permanently.