My drive keeps running out of space even though I barely have anything installed. I checked the disk with WinDirStat and found that hiberfil.sys is using around 30 GB. What is this file for, and is there a safe way to reduce or remove it? This Windows installation is fairly old, although I'm not sure whether that affects the file's size.
3 Answers
Make sure the file is actually hiberfil.sys and not pagefile.sys. The page file is used for virtual memory and should generally be managed separately rather than deleted. If it turns out to be pagefile.sys, you can adjust its size in Windows’ virtual memory settings, but reducing it too far can cause stability problems.
That’s the Windows hibernation file. Its size is largely based on how much RAM your computer has because Windows saves the current system state there when you hibernate. You can disable hibernation to remove the file and reclaim the space, but you won’t be able to use Hibernate afterward.
That explains it—I use Hibernate pretty often, so I’ll probably keep it enabled unless I really need the extra space.
If you rarely use hibernation, open Command Prompt as an administrator and run `powercfg.exe /hibernate off`. Windows should delete hiberfil.sys and return the space to the drive. To enable it again later, run `powercfg.exe /hibernate on`.
I checked again and it is hiberfil.sys, so the hibernation setting is the reason for the large file.